“Leaving a paper trail” is device for accountants or investigators to find out where the money went.

In the case of actual collectors of paper money, the paper trail is vital in knowing the history of a particular bank note you might be considering buying.

If you are buying a high-grade note, it might interest you to discover that it had sold before as a lower grade note. Figuring this out is possible because notes have serial numbers that can be recorded and traced.

Assembling this information, or blazing the paper trail, is Martin Gengerke, a professional in the field who originally introduced the Gengerke Census and now is taking it one step further called the Gengerke Census Lite.

It is geared to coin dealers and paper money newcomers to help them identify a note and assess its rarity. It offers a complete census of large-size type notes issued before the conversion to small-size notes in 1929. It also offers a complete census of National Bank Notes, which were issued by individual banks 1863-1935 with a federal guarantee behind them.

The Gengerke Census Lite is a cheaper alternative at $30 than the version with all the bells and whistles. It comes on a disk and is updated once each year. The full version costs $175 and is updated continuously and can be downloaded over the Internet.

If you have a budding interest in paper money, you might consider e-mailing gengerke@aol.com for more information.