2242 years / 7222 years = 31.044 % of time.

Why did I calculate?

If several lineages from a single baramin were preserved on the Ark, then it could give an unexpected signal in baraminological statistical analyses. A bit over a quarter of Earth history is before the Flood.* If a baramin diversified greatly before the Flood, resulting in several ‘kinds’ at the time of Noah, and the lineages remained separate and continued to diversify after the Flood, one might find clustering (associated with a specific lineage) within a larger cluster (encompassing the kind). Certainly, this pattern could happen with even post-Flood diversification; however, multiple ‘Ark kinds’ from a baramin is likely to increase the frequency of and intensify such a signal.

* My emphasis.

https://creation.com/created-kinds-vs-ark-kinds