Would the orphans % be number of orphans / total stakes (valid + orphans)
Yes.
for the last week.
date Starting balance Stakes Percentage orphans. orphan %
7/13 2546 5 .1963
7/12 2540 6 .2362
7/11 2537 3 .1182 1 25%
7/10 2532 5 .1975 1 17%
7/09 2531 1 .0395 1 50%
7/08 2531 0 0
7/07 2527 4 .1583 1 20%
7/06 2519 8 .3176
I guess 2500 is too small a number to quickly get an idea of the orphan rate, but that looks like 4 orphans out of 36 stakes, or 11% so far. The variance is huge, with your daily orphan rate ranging from 0% to 50%...