Since it's income tax season here in the USA, let me shout out "Tax Preparer" by HowardSoft. First developed by Jim Howard in 1979 for the Apple II, "Tax Preparer" was featured on a 1985 "Computer Chronicles" episode, with Howard appearing in-studio with Stewart Cheifet and Gary Kildall.

41 years later, Howard is *still* updating and releasing "Tax Preparer" for the PC. It's almost certainly the oldest continuously developed program featured on "Computer Chronicles."

https://howardsoft.com

HowardSoft (Home Page)

Developing tax and real estate software for personal computers since 1979, HowardSoft is known for its Tax Preparer and Real Estate Analyzer products. Tax Preparer supports 1040, 1065, and 540 returns, plus e-file for tax professionals.

Computer Chronicles Revisited 34 — Dollars and Sense, Bank of America's Homebanking, and Tax Preparer by HowardSoft

The Computer Chronicles discusses personal finance software.

Computer Chronicles Revisited