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Deinde, ne in posterum a XII kalendas aprilis aequinactium recedat statuimus bissextum quarto quoque anno (uti mos est) continuari debere, praeterquam in centesimis annis; qui, quamvis bissextiles antea semper fuerint, qualem etiam esse volumus annum MDC, post eum tamen qui deinceps consequentur centesimi non omnes bissextiles sint, sed in quadringentis quibusque annis primi quique tres centesimi sine bissexto transiqntur, quartus vero quisque centesimus bissextilis sit, ita ut annus MDCC, MDCCC, MDCCCC bissextiles non sint. Anno vero MM, more consueto dies bissextus intercaletur, februario dies XXIX continente, idemque ordo intermittendi intercalandique bissextum diem in quadringentis quibusque annis perpetuo conservetur.

[We therefore decided to continue to set a leap year in every fourth year (as is the custom) in order to prevent the equinox from falling back from 12 months - except in the centennial years, which will always have been leap years before now, and which we also wish to occur in 1600, but after that in the following years the centennial years are not all leap years, but in every four-hundredth year, whereby the first three centennial years will not be leap years but the four-hundredth year indeed will be, so that 1700, 1800, 1900 are not leap years. But indeed in the year 2000, a leap day should be inserted, in the usual way, by February having 29 days and in the same way in ensuing periods the leap day should be retained in each four-hundredth year.]