The chronology of the tomb monument's completion is not precisely known, but portions can be determined from various sources. According to the passing reference of a Florentine notary, in 1424 (by the Florentine calendar) part of the tomb was installed. Michelozzo's "Catasto" from July 1427 indicates that Michelozzo had been Donatello's partner for about two years (""due anni o incircha"") and that three-fourths of the 800 florin budget had been spent. To harmonize these accounts, one must conclude either that Michelozzo's chronology was imprecise, that Donatello received the commission before the partnership was formed, or that the 1424 date in the Florentine calendar falls in 1425 in the modern calendar.