As noted by The Oregonian's Betsy Hammond: "Oregon's student-teacher ratios, long some of the highest in the nation, rose to dramatic new highs of about 22 students per teacher in 2012-13, the state reported last week." Here is the accompanying graphic (pity there are not national averages to compare):
But does this matter? As with most things in social science the issue will never be entirely settled, but the weight of the evidence is solidly in the 'yes' column, something on which I have written extensively.
In fact the metric I think is probably the most appropriate that is directly ties to funding is the contact hours per student, which is the combination of school days and hours divided by class size. Both of which appear to be important empirically.