I used to think that the lists of ships for 1648, 1651, and 1652 were static

Back when I started one of my writing projects, "Dutch Ships in Various Operations During the First Anglo-Dutch War", I had assumed that the lists of ships, the 40 convoyers funded in 1648, the 36 cruisers funded in 1651, the 50 Directors' ships funded in 1652, and the 100 ships funded in 1652 were static, so that I could have one table for each. I would fill them in once and that would be enough. I know now that the ships funded by each increment changed over time. The first indication of that was when more ships were hired by the Directors to replace losses. I could also see that more ships were hired by the admiralties, also to replace losses, but also to replace ships discarded for various reasons. Dr. Colenbrander had the numbers of ships for Rotterdam, Amsterdam, the Noorderkwartier, Zeeland, and Friesland in his book, Bescheiden uit vreemde Archieven omtrent de groote Nederlandsche Zeeoorlogen, 1652-76.