Understanding the circulating supply of an NFT group.

I was looking at the data for the Waifu NFT parent on the SLP explorer (https://simpleledger.info/#token/a2987562a405648a6c5622ed6c205fca6169faa8afeb96a994b48010bd186a66). It says that there is a circulating supply of 257 after 210,000 were minted. Are these numbers not accurate for NFTs? It shows nearly 30,000 transactions, and my understanding was that there was an original supply of 30,000 Waifu.