20 Dollars

The P#30 series had an unusually long production run, with printing responsibilities split between the Canadian Bank Note Company and De La Rue at different points across the issue's lifespan — a dual-printer arrangement that can produce subtle but catalogable differences in ink saturation and paper stock between earlier and later dates. Specialists distinguish these by examining the quality of the fine-line guilloche work, where the two firms' outputs diverge noticeably under magnification.

Guyana's dollar had been pegged, floated, and devalued repeatedly before this series stabilized, and the note's longevity through 2018 reflects a period of relative monetary calm compared to the turbulence of the 1980s exchange crises.