Total 2006 topic Usage is Shown in the this file: 2006 TOPIC USAGE.mdb.zip
All of the topics that were reported in 2006 are shown in this table.
Inevitably, there are errors in this table. The idea is to get an approximate idea of the overall topic usage.
"MB" means "maybe used".
This table also shows the 'old topics' from 2005 that were still in use in early 2006. These topics are shown without a reference number.
The column, "First Date" shows the first reported date - some topics would have been in use before that date but never reported on the internet.
Similarly, the column, "Last Date" shows the last reported usage. Some topics might have been used for a few tests longer than this Last Date.
The column, "Time Used" shows the difference between the first and the last date.
Conclusions
Most topics seem to have been used for about 12 months, possibly a little more or a little less than 12 months but 13 months or more is rare and these are possible mistakes of some kind.
During 2006, the pool of possible topics was about 40 topics at any time.
During 2006, about 15 topics were selected from the pool to be used each test weekend. So, each test date shows 15 or fewer topics in use.
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