I'm leaning the other way. I think more singles. One group I know stats for off the top of my head is The Beatles. 1962-70 they released 22 UK singles, about a dozen EPs and half a dozen or so Xmas flexis, plus 'Hamburg' singles. Probably 40-plus 7-inch releases. LPs on the other hand numbered about 15 - no more than 20, anyway.

Assuming that type of output is typical, the number of 45s is around double that of LPs.

To take a later example, Michael Jackson's Thriller LP spawned about six singles, to just the one LP.