There is a formula to calculate number of rounds in https://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.186-5.pdf Appendix C.1. OpenSSL use it: https://github.com/openssl/openssl/blob/ee8772e3565a84fde9e2...

For 160-bit prime and security level 2^-80, 19 rounds is enough.