The number of species occurrence records for each year in the sampling period.
	Part of: Garretson A, Napoli M, Feldsine N, Adler-Colvin P, Long E (2020) Vernal pool amphibian breeding ecology monitoring from 1931 to present: A harmonised historical and ongoing observational ecology dataset. Biodiversity Data Journal 8: e50121. https://doi.org/10.3897/BDJ.8.e50121