This coin's own market cap as a percent of its whole category's market cap, at the same snapshot. The category total is the denominator — not the coins shown in this table — so these percentages do not sum to 100%.
FlagFlags a coin whose own 7d return is behind its category's while the category itself is outperforming Total3 and gaining share. 'Cannot tell' means one of those three inputs isn't banked yet. A category's 7d return is weighted by market cap, so a coin holding a large share of that cap is itself much of the benchmark it is measured against — its relative strength sits near zero and this flag tells you little about it either way. Its own share of that cap is shown beside it.