Haven't got the foggiest clue.  Still have potential, but every day crossed off the calendar without a soaker makes it rougher.  So instead of a guess, here is ten years of my August rainfall and NASS average county yields for the counties I farm in.  Kinda wishing now that I hadn't gone and done this...   There are definitely other factors involved, like planting dates and growing seasons that had worse than normal issues with SDS or other pests, but it seems that there needs to be at least one good August soaker here to have above-average bean yields....

                   Precipitation              Yield

2010               9.1"                       47.4

2011               1.4"                       38.5

2012               3.7"                        43     (late hurricane rains really saved our 2012 beans, after the corn was already zorched)

2013               .9"                          40.9

2014               3.9"                       48.4

2915               2.68"                     48.1

2016               6.35"                     55.9

2017              1.32"                      39.6

2018              6.25"                      58.1

2019              3.7"                        53.6

2020              zero.37"....