Part 2 of 3 Parts
Birth Data, Data Rating and Astro-Research

The Rodden Rating System

By DW Sutton

Subheadings: The Rodden Rating System    Data accuracy is always a problem    B, C and D data    A rated data    Birth certificates    AA — birth certificate — data    Oddities with the time on the birth certificate    Rounding off the birth time    On the hour births    AA birth times — an investigation    There’s a flaw in the AA rating classification    Rating the accuracy of a AA birth time

Introduction: Birth times and birth certificates play a vital role in astrology and Birth Data, Data-Rating and Astro-Research is essentially an investigation into the recording and accuracy rating of birth data over the past 100 years.

During the 1970’s Lois Rodden and a handful of dedicated data collectors realized that much of the birth-data being used by astrologers was simply hearsay, rectified guesswork, downright dodgy or wrong — and this woeful situation adversely affected the scientific status and credibility of astrology. Gradually the need to verify and validate existing and new birth data developed into a vital issue affecting the international astrological community. The result was The Rodden Rating System. To quote Lois Rodden from her book Profiles of Women,

The Rodden Rating System of accuracy developed quite spontaneously at the time that Profiles of Women was in the process of publication (in late 1979), and has been used in each of the successive data collections. Collectors around the world have recognized the simplicity and efficiency of the rating system.

The Rodden Rating System

Data accuracy is always a problem

We data collectors (and I would add those doing astro-research) become very skeptical as the very nature of recorded information is such that human error accumulates in spite of the best intentions. There is no data book or collection that is without flaw. Though it is possible to find cases when the birth certificate is in error, AA data is the best evidence we have of accurate birth information.

‘A’ data may or may not be accurate. Please keep in mind that public figures, especially politicians, answer a public question to be accommodating rather than specific in regard to their birth time. The answer of 8.00am, midnight, 6.00pm, just before noon, or variations thereof may be gracious but totally inaccurate or the time given may be approximate. The chance of accuracy is better when the public figure is a client of an astrologer who requests data from birth records.

‘B’ data may or may not be accurate. A person may lie about their age in their autobiography, and authors lean toward descriptions of a wild and stormy night. Literary license may be suspected unless the authors specify their source of information. Biographers who market scandal and gossip may actually create misinformation for the sake of shock value.

‘C’ data may or may not be accurate. Until a source can be traced there is no way to know if this data has any validity. When magazines and journals are quoted without the original source they may only be considered as reference; i.e. data from Profiles of Women is not a source but a reference.

‘DD’—Dirty Data—is presented for reference only and often stimulates correspondence that leads to correction and confirmation. As we astrologers work together for the good of our field, we all benefit, improving our data base worldwide.

She ended her explanation of the various data classifications with a plea — ‘Give the source of your data — and put the source on every chart.’

There’s no doubt that the development of the Rodden Rating System was the best thing to happen to astrology in the second half of the 20th Century. Three cheers for Lois Rodden. Now, when new or old birth data is made available, the person providing the data must state their source and those wishing to use the data can rate its authenticity and accuracy — particularly the accuracy of the birth time. This practice of stating the source of the data was rarely done prior to 1950.

Lois Rodden also did everyone a big favour by applying her rating system to all the older US data she had collected. This came from astrological organizations like the Church of Light, data collections like Sabian Symbols, and astrological magazines that were very popular during the 1930s and 1940s. This was a huge task — she collected thousands of data over many years — that in the end revealed just how undisciplined the astrological community was in the first half of the 20th century. While some pre-1950 data was sourced to birth certificates, birth records and family records and given an AA rating most of it was so poorly sourced it had to be given a C or DD rating — which meant that it was made up, speculative or ‘wrecktified’.

Now the astrological community reveres AA birth data — the birth time has been documented on a birth certificate or family record — but the evidence reveals that most AA data is best described as almost accurate and is not accurate enough for those research projects requiring an almost precise ascendant degree.

B, C and D data

‘B’ data comes from a biography or autobiography and it could be argued that Chuck Berry's 6.59am birth time — as given in his autobiography — is the time recorded on his birth certificate — and its probably much more accurate than many of the 7.00am birth times recorded on birth certificates. But because it comes from an autobiographical source its not eligible for astrological research. And its worth noting that birth data with an A rating is often much less precise than some of the data stated in an autobiography or biography that gets a B rating, but...in The Eddie Fisher Story the author Myra Greene claims that the singer was born at 7.45am and the birth certificate states 7.42am. So biographers do get it wrong.

Comedian Andy Kaufman gave Mary Mackenzie 6.03pm and then he told Shelley Ackerman 6.30pm. His biography Lost in the Funhouse states 2.00pm. So which time is right? 6.03am looks interesting but what time is recorded on the birth certificate? Times like this get a C rating — the C stands for caution. The time is undocumented and ambiguous and you should be very cautious.

In Data News #28 Lois Rodden presented the birth-data for Michael Blake (author of Dances with Wolves and commented: We don't have the time for the star and director, Kevin Costner, for whom I’d speculate Sagittarius rising. But Costner's birth certificate time — 9.40pm PST — gives 25° Virgo rising. This practice of taking a guess at the sign on the ascendant is a very unscientific way of getting a birthchart, but you might occasionally get it right.

Astrological data that has two or more unsubstantiated quotes is rated D for dirty and very often the birth time is a speculative guess or rectified. Much of the older data from the 40s and 50s has a dirty data rating simply because it was rectified and astrologers did not note the source of their data, but the practice of taking a guess at the birth time is still around today.

Doris Chase Doane in Progressions in Action used a birth time of 2.00am for Dr. Benjamin Spock. She got it from Marion Drew who (probably) speculated that the Moon — the astro-marker of nurturing — was in the 5th house (children) and took it from there. Spock's birth time is unknown. Joan Quigley, Nancy Reagans astrologer, used a rectified time for Ronald Reagan that gave 25° Sagittarius on the ascendant. During the 1940s Carroll Righter used a chart with Cancer rising: And Mildred Schuler at the Church of Light used a birth time of 1.20am — sourced to a close friend of the family — that gave 21° Scorpio on the ascendant. But there's no time on Reagans birth certificate so his fifty-six (56) birth times are all speculative. This is a world record and needless to say each one gets a Dirty Data rating.

‘A’ rated data

‘A’ rated data comes from memory. It’s accurate in the sense that it’s been quoted by the person, their kin or an intimate associate. But the evidence reveals that many people don't remember their precise time of birth, the time they give is often rounded off and mothers memory is rarely 100 accurate.

Writer Jean Auel gave her birth time to Wayne Moody as 5.20pm. Her birth certificate states 5.35pm. Cher gave her birth time to Kelly Quinn as 7.31 am. Her birth certificate states 7.25am. Dory Previn stated midnight in her autobiography Midnight Baby. The birth certificate states 12.05am. Writer Neale Walsch gave 4.23am to Tashi Grady, but when Stephen Przybylowski checked the birth certificate it stated 4.19am. Madeline Khan gave 6.19pm to Lloyd Cope, but her birth certificate states 6.07pm. Singer Gregg Allman gave 3.03am to Kelly Quinn but his birth certificate states 3.39pm. Singer Annie Lennox gave 11.30pm to Babs Kirby, but her birth certificate states 11.10pm. Actress Bernadette Peters gave 11.15pm to IC McRae, but her birth certificate states 10.45pm. Ralph Edwards, creator of, This is Your Life, gave Doris Chase Doane 9.13am, but his birth certificate states 9.00am: And in her autobiography Starving for Attention Cherry Boone O’Neill (daughter of Pat Boone) gave her birth time as 8.41am. Her birth record states 8.08am.

An investigation into the A rated data presented by Frank Clifford in his data book — British Entertainers — clarifies the state of play in England, Scotland, Ireland and Wales. The book presents 286 A rated data — mostly from mothers memory — and a breakdown of the data reveals that: 127 of the births occurred on the hour (44.9%); 67 occurred on the half hour (23.6%); 35 occurred on the quarter hour (12.4%); and 31 occurred on the 10, 20, 40 or 50 minute mark (11%). 26 were for a more precise minute (9%) — the Virgo contribution. With 68.5 of the births occurring right on the hour and half hour you can safely assume that most of these birth times have been rounded off. George Harrisons sister clarified the situation in England when commenting on her brothers birth time in February 1943: ‘In those days, before digital clocks and all that, spoken remarks re time were approximated to the nearest 5 minutes or so — ten off or a quarter after and such’.

The Rodden Rating System gives a birth time from someone's memory an A rating. It may or may not be accurate — but the evidence indicates that the most frequently stated times are the hour, half-hour and quarter hour. Some A data looks really good — and some people do remember the time recorded on their birth certificate — but there's always an element of doubt until its sighted. Memory failure can occur. So the message is clear — beware of birth-data coming from memory — the messenger can get it wrong. Agatha Christie got it right when she gave her birth time as 4.00pm — with the clarification hearsay.

Birth certificates

History reveals that the documentation and registration of a child's birth was a quite common practice — but certified birth certificates are a very recent invention. Abraham Lincoln didn't have one — and the only existing record of his birth date is an autobiographical sketch in which he states February 12, 1809. Cleopatra didn't have one either, but her birth in 69BC in Alexandria, Egypt was recorded by priests in hieroglyphic text. The registration of births it seems is just a matter of when and where you were born. The authorities in some countries — China, Egypt, Greece — kept tabs on population numbers for military and tax purposes, but there is no birth record for Genghis Khan because Mongolia didn't keep birth records when he was born.

In the US prior to 1900 births frequently went unrecorded or were noted by doctors, midwives, church officials or family members. Then from 1900 to 1946 the US Census Bureau designed standard birth certificates and generally sought to improve the accuracy of vital statistics. In 1946 this responsibility passed to the US Public Health Service. They issued a standard form called a Certificate of Live Birth, however individual states can create their own.

Most countries now have statutes and laws that regulate the registration of births. Most often its the responsibility of the mothers physician, midwife, hospital administrator — or the child's parents — to properly register the child's birth with the appropriate government agency. The official birth document is then stored with the agency. In the US the physician attending the birth — or hospital administrator — is required by law to complete the birth certificate form and forward it to a local or state registrar who stores the record and issues certified copies when requested. Your birth certificate provides prima facie evidence that you were born, but in 2008 it was estimated that 51 million babies — more than two-fifths of those born worldwide — were not registered at birth.

In most countries the attending physician or midwife records a child's hour and minute of birth on a birth certificate. On occasions an interested third party with a stop watch may record an even more precise time; but different countries have different procedures and different accuracy standards — and some record the birth time on a birth certificate and some don't.

In the US, Italy, France and Scotland and most countries in the Euro Zone a very precise time of birth is recorded on a birth certificate. Japan started entering the birth time on a birth record in 1947 and most countries in South America record the birth time on a birth certificate. But England and Australia don't. These countries have birth certificates but the birth time is not documented on the certificate. It is documented (by someone) on the hospital records or the baby's birth announcement or baby card.

AA — birth certificate — data

Birthcharts require birth times and an accurate chart requires an accurate time. But birth times have always been the fly in the ointment and the history of astrology — while documenting a colorful array of personal and mundane predictions that apparently came true — forgets to mention that the birth times and the birthcharts were never accurate enough to get it right. Psychic skills — not astrological skills — made the amazing predictions. But in the past 100 years there's been a dynamic shift and now — for the first time in history — the scientific astrologer has easy access to accurately timed births, accurately constructed charts and accurately documented life stories. And this means s/he can use the scientific method to gather astrological facts. Its all because someone decided to document the birth time on a birth certificate — and Marion March suggested to Lois Rodden that this documented birth time be given an AA rating.

The document that documents the birth time can be a birth certificate, other personal effect, birth registration form or civic record — and the documenting can be done by a physician, midwife, parent, family member or birth registrar. But — whatever — its automatically given AA status. Unlike memory the ink on the page is not inclined to fade or forget.

Documented AA data is without a doubt the most accurate data of all and this makes it eligible for astrological research projects, but the presumption that all AA data must be absolutely accurate is a little misguided. At best it is almost accurate. You see a lot of birth times that automatically get AA ratings because they are documented. They fulfill the AA criterion but actually have been rounded off and they're not accurate enough for research and other purposes. This particularly applies to most 19th Century data, but a quick browse of 20th Century data — especially the data coming from France and Italy via Michel Gauquelin and Grazia Bordoni and the data from Scotland — reveals that too many people are being born right on the hour and half hour. And the same observation applies to birth times in the US prior to 1950.

The accuracy of the birth time recorded on a birth certificate depends upon a variety of factors all of which are beyond the astrologers control — unless s/he does the timing: And the hard evidence indicates that some birth times are much more accurate than others. The more accurate the birth time the more accurate the birthchart and the astrological data it provides — and this means that only the most accurately timed AA charts should be included in every astrological research project. It also means that Rodden's AA data classification requires some fine tuning.

Oddities with the time on the birth certificate

Most US birth certificates record a birth time, but there have been odd instances where: No time was recorded, there were two different times on two different birth records, the time was blurred and difficult to read, the am/pm time designation was omitted and the time was disputed.

There's no time on Christopher Reeves birth certificate and he gave three (3) different birth times — 3.12 am, 3.14am and 3.30am — to three (3) different astrologers. And Patrick Duffy gave his birth time as around 9.00am, but when Nikki Hall called the Records Bureau there was no time on the birth certificate. There was no time on James Dean’s birth certificate either until March 2006 when a copy obtained by Stephen Przybylowski stated 9.00am. But his birth announcement and baby card state 2.00am so now he's got two (2) birth times. Elizabeth Taylor remarked that she, Dean and Rock Hudson were all born at 2.00am, which is nearly right. She was born at about 2.00am according to her mother and Rock Hudson has 2.1 Sam recorded on his birth certificate. So the 2.00am time Dean told her is the time on his baby card.

Christopher Boyce has two (2) different birth certificate times — a very odd situation. Contemporary Sidereal Horoscopes quote the birth certificate for 2.10pm and Victoria Shaw quotes the birth certificate for 2.01 pm. Maybe its a transcribing error. And astronaut John Glenn has two different birth times recorded on two official documents — one for 3.00pm and one for 4.00pm. This oddity was sorted out when the 4.00pm birth certificate time was validated by the records bureau. Eva Braun has two different birth times too. Her birth certificate gives 12.30am and her birth announcement states 5.30am.

On rare occasions the time on the birth certificate has no am or pm designation. Joe DiMaggio's birth certificate states 7.00 PST. There's no am or pm, but Rodden considers military time a safe bet which makes it am. There's also the chance that the time on the birth certificate can be so blurred or smudged that its difficult to read. The time on William Schirras birth certificate was so blurred that two reputable data sources gave two different times. Contemporary Sidereal Horoscopes stated 11.55pm and Michael Gauquelin stated 4.55pm. Schirra clarified the dilemma when he gave Pioneers of Tomorrow 4.55pm. And Nat ‘King’ Coles birth time was changed from 9.00am to 3.00am when the numbers on his birth certificate were closely examined.

There are also instances where the time on the birth certificate has been disputed. Singer Brenda Boozers birth certificate states 4.45pm yet her parents insist she was born in the am: And Norman Mailers birth certificate states 9.05am yet his mother states 7.00am — claiming that she inadvertently recorded the 9.05am time on the birth certificate.

Rounding off the birth time

Observation and research reveals that the practice of rounding off the birth time to the nearest hour, half hour and quarter hour was common in all countries in the 1 800s. And the practice of rounding off the birth time to nearest five minute increment was common during most of the 20th Century.

In Data News #24 Lois Rodden reported:

In the Gauquelin books the 18th and 19th century data seems to be mostly rounded off to the hour, with the 20th century data rounded off to the nearest 15 minutes and the most recent data (1985) often to closer times, apparently to 5 minute increments, especially in Belgium and Italy. With these kinds of records, we tend to consider a 2.00am, or a 4.00am, or even a 6.45pm time as an approximate figure, accurate to within 5 minutes one way or the other.

And Grazia Bordoni reported that in Italy more births are given as Noon than any other hour of the day. This means that most of the older AA European data is too dodgy for astrological research.

Research into the AA birth data presented by Frank Clifford in his data collection — British Entertainers — clarifies the situation in the United Kingdom. Of the 374 AA rated birth times 58 occurred on the hour, 66 on the half hour, 32 at 15 minutes past the hour and 31 at 15 minutes to the hour. The mathematical expectation in each case was 6. Only 29 births occurred on a minute ending in a 1, 2, 3, 4, 6, 7, 8 or 9. The mathematical expectation was 288 so the evidence reveals that the birth time was being rounded off. To repeat the explanation given by George Harrisons sister: ‘In those days (1943 — and much later), before digital clocks and all that, spoken remarks re time were approximate to the nearest 5 minutes or so — ten off or a quarter after and such’.

An investigation into 600 birth times (not AA data) used in the original Church of Light research revealed that 240 occurred on the hour and 106 occurred on the half hour. In both instances the mathematical expectation was 10. Of the 387 participants born in the 1 800s or earlier 150 were born on the hour and 90 were born on the half hour. And of the 213 participants born in the 1900s 63 were born on the hour and 43 were born on the half hour. A more recent investigation involving 600 randomly selected AA birth data revealed that 79 were born on the hour and 55 were born on the half hour. So the situation during the 20th century did slowly improve — and the most recent evidence reveals that the tendency to round off the birth time has almost ceased.

Since 1980 the recording of birth times in France, Italy, Scotland and the US has become much more precise. Most births in these countries are now timed to a precise minute and the number being timed to an exact hour or half hour has reduced significantly. And that's good news for astrology.

On the hour births

A birth record that states that the birth occurred right on the hour presents a dilemma. Did it or didn't it? Or has it been rounded off? A birth that occurs at two minutes to the hour or three minutes past the hour did not occur on the hour — and if its been rounded off there's no way of knowing just how much rounding off has taken place. Experienced astrologers tend to view on the hour births with a high degree of suspicion. Research also reveals that too many births are occurring exactly on the half hour — a sure sign that they're being rounded off too. And while too many are occurring at 10, 20, 40 and 50 minutes past the hour its reasonable to assume that in these instances the birth time will be accurate to within plus or minus two or three minutes.

Lois Rodden commented:

Actually, Noon and Midnight are the two times of which I am most suspicious, with 6.00am and 6.00pm a close second. People are born at these times, my grandson Jordan was born 30 seconds by my stop-watch from 1.00pm PDT, but when someone who is indifferent to the time of birth goes to the registry office, sometimes days or even months (or years) after the event, that person may arbitrarily say Noon because the baby was born in the daytime, or Midnight because they remember getting up in the night.

The Michel Gauquelin data reveals that just about everyone born in the 19th century was born right on the hour and the hard evidence also reveals that the Church of Light in its various research projects used an abnormally high number of charts that were timed to the hour.

Of the 600 hundred charts used in the Church of Light’s Doctor, Writer, Telephone Operator, Lawyer, Movie Star and Waiter research projects 240 were timed to the hour, 106 were timed to the half hour and 254 were timed to another minute of the hour. This means that 24 people in 60 — or 40 of the participants — were born on the same minute of the hour, when theoretically there should have been 1. So you can conclude that something was awry. If you take a sample of 60 people the probability of 10 being born on the same minute (of any hour) are 1 in 6046617600 billion.

In these Church of Light research projects five (5) of the participants were born in the 17th or 18th centuries — 382 were born in the 19th century — and 213 were born in the 20th Century. Of those born between 1900 and 1929 eighty seven (87) were born on the hour. 40 and 42 were born on the half hour. This evidence from the past reveals that far too many babies were being born just as the clock struck the hour. It really was amazing. The Church of Light gathered birth data from its membership so it’s unknown if the birth time came from the birth certificate or someone's memory.

AA birth times — an investigation

An investigation involving 600 randomly selected AA birth times was conducted to learn how many births actually occurred on each minute of the hour. The birth minute — not hour — was the time factor under consideration. Most of the births occurred in the US between 1930 and 1970 and the birth time was documented on a birth certificate. Here’s what the investigation revealed:

Births that occurred on the hour	79
Births that occurred on the half hour	55
Births that occurred on the 15 minute mark	42
Births that occurred on the 45 minute mark	33
Births that occurred on the 10 minute mark	30
Births that occurred on the 20 minute mark	20
Births that occurred on the 40 minute mark	28
Births that occurred on the 50 minute mark	19
Births that occurred on the 5 minute mark	17
Births that occurred on the 25 minute mark	16
Births that occurred on the 35 minute mark	16
Births that occurred on the 55 minute mark	26
Total number of births occurring on the 1, 2, 3, 4, 6, 7, 8, and 9 minute marks	219
Total Births Considered	600

It's unknown if nature plays favorites with certain minutes of the hour — or certain hours of the day — but theoretically, in this investigation, 10 births (600 divided by 60) should have occurred on each minute of the hour. 10 is the mathematical expectation — and the number of actual births is the actual value. This investigation reveals that 79 births actually occurred on the hour and 10 was the expectation so probability aside we can safely say that something was going wrong with the recording of the birth time. The indicated figures speak for themselves and in every instance the number of births occurring on the 1 ,2, 3, 4, 6, 7, 8,and 9 minute marks was below the expectation of 10.

The investigation also confirmed what most astrologers suspected. The number of births that occurred in the 19 minute period from 9 minutes to the hour to 9 minutes past the hour was 191 — 190 was the expectation: And the number of births that occurred in the 13 minute period from 24 minutes past the hour to 26 minutes to the hour was 129 — and 130 was the expectation. The numbers reveal that a large proportion of the births that occurred on the hour and half had been rounded off and that any birth that occurred on the hour could be a given a plus or minus nine (9) minute margin of error and that any birth that occurred on the half hour could be a given a plus or minus six (6) minute margin of error.

There’s a flaw in the AA rating classification

With all documented birth times being eligible for an AA rating and with many having their real accuracy disputed the AA rating classification has a flaw that needs to be fine-tuned.

The Rodden Rating System automatically gives a documented birth time an AA rating. Its documentation on a birth certificate, birth record or civil register automatically makes it eligible for an AA rating — and its inclusion in astrological research projects. But the evidence reveals that many birth times — especially those given as on the hour or half hour are approximate and those timed to the 5, 10, 15, 20, 25, 35, 40, 45, 50 and 55 minute marks — have been rounded off and their accuracy status requires further clarification. There's no doubt that some AA birth times are far more accurate than others.

This particularly applies to the 18th and 19th century data collected by Michel Gauquelin. To quote Lois Rodden again: In the Gauquelin books the earlier data, of the 18th and 19th century, seems to be mostly rounded off to the hour, with the 20th century data rounded off to the nearest 15 minutes and the most recent data (after 1960) ... apparently to 5 minute increments, especially in Belgium and Italy. With these kinds of records, we tend to consider a 2.00am, or a 4.00am, or even a 6.45pm time as an approximate figure, accurate to within 5 minutes one way or the other. The worst quote of all is Midnight, as there is a 24-hour difference between midnight starting the day or midnight ending the day. She also commented: Actually, Noon and Midnight are the two times of which I am most suspicious, with 6.00am and 6.00pm a close second.

Well, this investigator is suspicious of any birth that occurs on the hour — not just noon or midnight, but any precise hour of the day. And he doesn't have a lot of confidence in the accuracy of births that occur on the half hour either. He knows some do, but he doesn't know which and the hard evidence provided by birth certificates reveals that far too many people are being born right on the hour or half hour. Of course the astro-research worker can discriminate with what data s/he chooses to include in a particular research project, but that misses the point. All AA data is eligible.

This inadequacy in the AA classification of Rodden's Rating System needs to be fixed. Astrological research will only provide authentic astrological evidence when the birthcharts it investigates are very accurately timed — and the most accurately timed charts are those where the birth minute ends in a 1 ,2, 3, 4, 6, 7, 8, or 9. These charts will not be 100 precise, but at this stage of the game they will provide the astrological research worker with the most reliable astrological information — and in the end that's what s/he, the astrological community and humanity wants.

Rating the accuracy of a AA birth time

A child's life commences the moment it takes its first breath — and the birthchart should be constructed for this moment in time. But the birth certificate never records this time precisely. Theoretically it may — but the astrologer is none the wiser. The facts are: (1) astrologers work with birth times recorded by other people — (2) these times are rarely — very rarely — 100% accurate — and (3) the astrologer doesn't know just how accurate the recorded time really is.

As the astrological starting point the birth time plays a crucial role. It not only determines the layout of the constructed chart it influences the accuracy and authenticity of the information provided by the chart — and the Rodden Rating System was devised to address this issue of birth time accuracy. The system gives any recorded birth time an AA rating but research into thousands of AA recorded birth times by this researcher forces the conclusion that the accuracy of the birth times within this AA category varies greatly. So based on this research he's modified Rodden's AA category to permit a more accurate classification of any birth time that qualifies due to its birth certificate status.

AA-1 — any birth time that ends in a 1, 2, 3, 4, 6, 7, 8 or 9 number of minutes. The evidence indicates that these are the most accurate charts and the AA-1 indicates the recorded birth time has a + or — one (1) minute margin of error.

AA-2 — any birth time ending in a 5, 10, 20, 25, 35, 40, 50 or 55 number of minutes. These are the second most accurate charts and the AA-2 indicates that the recorded birth time has a + or — two (2) minute margin of error.

AA-3 — any birth time ending in a 15 or 45 number of minutes. The evidence indicates that some rounding off could have occurred and the AA-3 indicates that the recorded birth time has a + or — three (3) minute margin of error.

AA-5 — any birth time occurring on the half-hour — the 30 minute mark. While some will be accurate many have been rounded off and the astrologer doesn't know which. The AA-5 indicates that the recorded birth time has a + or — five (5) minute margin of error.

AA-7 — any birth time occurring on the hour — any hour of the day. The evidence in 2010 indicates that the practice of rounding off the birth time to the nearest hour was common during the 20th century and while some births will occur on the hour the astrologer doesn't know which. The AA-7 indicates that the recorded birth time has a + or — seven (7) minute margin of error but in some instances — particularly with older (18th and 19th century) data — this margin of error may need to be increased significantly.

Copyright 2014, DW Sutton, light.org

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