Joanne effect in 1999? : LUSENET : TimeBomb 2000 (Y2000) : One Thread

I surfed to cory hamasaki's site.( Read about the "Joanne Effect" in his report #91. My questions to all: 1. will this really work that way? 2. If not - why not? 3. If so Does not the y2k start a tad early? 4. If it DOES work - How about the folks that use a fiscal yr and a 2 or 3 year forecast field? ( Look back - current - next)Would we have heard of it by now? 5. Wouldn't someone notice some of the effects of Joannes'GIGO by now if it has hit an internal date check system somewhere? 6. Would you even know it was wrong until the bean counters did their magic? This assumes that your machine keeps machining and just stores bad data somehow. I can't see how it won't make TSHTF but I may well be missing something. I feel that we have a BIG problem with yk2 and I have prepared as best I can for me and mine, however I am curious about this Joanne effect thing.

-- sweetolebob (, September 10, 1998


I think banks will have problems as early as Jan 99 due to this. I prefer to call it the forecasting effect, Jo Anne objects to her name being attached to it. Unless you want to be without money I would get some out now. Why do I think this? Well, not only is there the forecasting effect but there is also the habit of using 99 to signal end of file. It should be interesting.

-- Amy Leone (, September 10, 1998.

Re: "If so Does not the y2k start a tad early?", it is important that everyone understand that indeed The Y2K Problem will actually start in 1999. The Joanne Effect is one aspect, govts/businesses fiscal year 2000 rollovers (many in April 1999), "spike dates" like Sept 9, 1999 ("9/9/99"), etc. But as important, if not MORE important: the reaction of John Q. Public when Y2K actually become real to them. Right now, its just another topic in the news. When Granny doesn't get her disability check due to "Y2K computer problems", then you had better believe that the Y2K problem will have landed. Get cash! Get stored food! Prepare, it is coming!!!

-- Joe (, September 10, 1998.

I would doubt that a value of 090999 in a MMDDYY date field would cause programs to detect End Of File (EOF). Normally the ENTIRE field is checked for 9s ie would have to be a value of 999999. Furthermore it is less likely that a date field would be used for a key field check, it would usually be something like a unique value field such as "Account Number". If a program checked the YY only part of a field to test for EOF (very unlikely) it would fail at the beginning of 1999 or when 1999 dates first started appearing on the file.

-- Richard Dale (, September 10, 1998.

You could see a few problems on April 9th, though. It is the 99th day of '99.

-- Gayla Dunbar (, September 10, 1998.

The 99th day would become relevant if the julian day format were used ie YYMMM, the value stored would be 99099, again the leading zero might save the day.

-- Richard Dale (, September 10, 1998.

Medicare just screwed up 570 million in payments due "a computer problem when they tried to fix the program for year 2000."

Supposedly (and the news media didn't give details) the problem lies in miscalculating the copayments made over the past few weeks. "Congress is going to work out a solution."

-- Robert A. Cook, P.E. (, September 10, 1998.

Richard, I see your point about "090999" not being seemingly likely to trigger a special procedural action ("999999" being more likely), but you have to consider that a programmer who wanted to use "9"s to signal a special action had to stay within bounds of whatever other software routines might be checking the data. An entry of "999999" might get kicked out due to validation checking of the month (not 1..12) and day (not 1..31). So, in fact "090999" would be a visually easy to see flag for a human, and perfectly legit data for any lurking validation routine.

-- Joe (, September 10, 1998.

Last April 1, Japan, Canada, and New York State began their fiscal year 1999. I think if there had been a problem, we would certainly know it by now...especially if N.Y. State's welfare recipients and retired government employees had not received their checks. On October 1, our federal government starts fiscal '99. Believe me, everyone'll hear about it if we seniors do not receive our Social Security insurance payments! Hmmm....then there are our four past Presidents receiving "Uncle" checks, too!

-- Holly Allen (, September 10, 1998.

Holly, by definition the "Joanne Effect" tests to see whether a date is within the range of the current fiscal year BASED ON CALENDAR YEAR END-POINTS (at least as I understand it). We will not see this effect until the "greater" endpoint involves the year 2000, in which case if a program is comparing 12/31/1998 with 1/1/2000, there will be no problem; but if its comparing 12/31/98 with 1/1/00, then indeed there will be (the so-called Joanne Effect).

-- Joe (, September 10, 1998.

This is, of course, not a problem if the program uses "windowing" in which case it would know that 1/1/00 IS > 12/31/99. This is a more of a patch than a fix, but not really a problem for fiscal years, until you reach the edge of the window. Many programs do employ such a windowing scheme.

-- Mike (, September 10, 1998.

Mike, only works for remediated programs.

If they haven't fixed it by the time their fiscal year ends in 2000, then it can cause a problem.

Means we have to start being concerned next Jan 1.

-- dont (ask@meto.tell), September 11, 1998.

The "Jo Anne Effect" (named after me by Cory Hamasaki) refers specifically to accounting software, and fiscal years that span two calendar years (1999 and 2000).

Many companies have a fiscal year-end that is not the calendar year-end. March 31, April 30, June 30, and other dates are popular for year-ends. When a company has a year-end of this type, there may be difficulties with the accounting software when the company attempts to "close" fiscal 1999 and "open" fiscal 2000.

Picture a company using a 1993 version of some accounting software, running it on a network of 486's. This company thinks they have until December 1999 to update their hardware and software, but they have not remembered that their fiscal year-end is, say, February 28 1999.

The accounting year-end "roll-over" (closing), in this example, would instruct the computer to move all fiscal 1999 transactions to an "old" file, and open up a "new" file with transactions dated between March 1, 1999 and February 28, 2000. But if the software only recognizes a 2-digit year, what will it do?

Is March 99 before Jan 00, or after? Will the software allow the new fiscal year to open, or will it give some kind of error message? If the fiscal year does roll over, will the transactions sort properly or will some of them be "lost"?

I expect that the "Jo Anne Effect" will be a big slap in the face for a lot of companies, early next year. They will see that they can't wait until December 31 1999 to fix their problems - everything really should be done before the fiscal year end.

If anyone has any questions, please feel free to email me.

-- Jo Anne Slaven (, September 12, 1998.

Jo Anne: Thank you for posting a clarification of the effect. Now I understand it. I read the posting that states that you don't care for the name. I am the one who first asked the questions in reference to the effects and as such it falls to me to apoligize for the use of the name, and for getting your name wrong to boot. As a transplant I don't claim to be a Southern Gentleman but after all this time some manners have rubbed off.


I do hereby offer a thousand humble apologies to you and to all members of your family for ten (10) generations on either side. I meant no harm to anyone.

I really do appreciate your taking time to set me straight as regards the "Forecast Effect".

S.O.B. (LA)

-- sweetolebob (, September 13, 1998.

Thanks, Jo Anne for the posting. We are all here trying to learn as much as we can. I too have heard that you are not thrilled with the use of your name in conjunction with this "effect", and I can understand that. It almost gives the impression that you had something to do with "the problem." Believe me- we know better and we are so thankful for anyone who helps to alert the public about what is going to happen. Thanks for ALL of your efforts!!

-- Gayla Dunbar (, September 13, 1998.

Jo Anne : Thank you for your forsight and "label". I realize it isn't convenient, nor was it at all intended that the rest of us borrowed to describe a problem we couldn't define.

But please understand that by giving it (this one accounting problem) a clear label, we can begin talking about it. And in, fact, as you can see by the above postings, some of us couldn't actually understand it until it was expressed and defined. "What is this problem?" has to be understand before someone can find out if they are susceptible, if they have it, and if they have solved it.

To that end, you have greatly helped all of us. Thank you.

-- Robert A. Cook, P.E. (Kennesaw, GA) (, September 13, 1998.

One observation: This Y2K problem is one that is very specific, very well confined to a particular type of software, and very well understood. "Fix-on-failure" may actually work with this problem for those companies that have not fixed it ahead of time. But note that this is very much the Y2K problem EXCEPTION, and in early 1999 when this Y2K problem is fixed in a relatively straightforward manner, beware of those who would point to it and declare that all Y2K problems can be so easily handled!

-- Joe (, September 14, 1998.

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