<Li> 1969: The new treasury seal appears on all denominations, including the $20 . </Li> <Li> 1977: A new type of serial - number press results in a slightly different font . The old presses are gradually retired, and old - style serial numbers appear as late as 1981 for this denomination . </Li> <Li> 1992: Anti-counterfeiting features are added: microprinting around the portrait, and a plastic strip embedded in the paper . Even though the bills read Series 1990, the first bills were printed in April 1992 . </Li> <Li> September 24, 1998: Received a completely new appearance to further deter counterfeiting; the picture of the White House was changed to the north side view . A larger, off - center portrait of Jackson was used on the front, and several anti-counterfeiting features were added, including color - shifting ink, microprinting, and a watermark . The plastic strip now reads "USA 20" and glows green under a black light . The bills were first printed in June 1998 . </Li>

When did they start putting strips in money