Non-directed kidney donors are increasing (and are increasingly important)

Here's a story on the increasing number of non-directed kidney donors: Amid organ shortage, altruistic kidney donations increase but bring forth ethical debate

This line caught my eye:
 "It's difficult to pinpoint a single reason for the uptick, but more than 50 percent of altruistic donations ever performed -- 1,374 as of April -- came after 2009, when numbers of traditional living donors started falling."

I am only speculating, but I'm guessing that the relatively small drop in live kidney donation has to do with the recession: when times are hard, it's harder to arrange time for a kidney surgery, since we don't allow donors to be compensated, and aren't even as good as we should be at covering their costs.
As for the growth of non-directed donations since 2009, that's when the first non-simultaneous non-directed donor chain was reported in the New England Journal of Medicine, and that and other long chains since then may have garnered enough publicity (such as this and this) to spread the word to potential donors.

In any event, chains started by non-directed donors are an increasingly important part of kidney exchange today, for reasons explored here.