In Wed, April 3, WSJ section/ page... b3. at end of article, ". Last year, Tesla collected. $ 40.5 million -about 10% of its total revenue ---- selling credits earned from states to other auto makers..". Mike Ramsey
Awkwardly phrased, but these are revenues from sale of the emissions credits that Tesla is awarded by states for selling zero-emission vehicles. Every car manufacturer selling in California and some other states has to have a certain minimum mix of zero- or very low-emissions cars in the mix. If the OEM misses, they can make up the shortfall by buying credits from car companies, like Tesla, that over-complied.