In 2023, the BioWorld Drug Developers Index (BDDI) concluded the year down 11.35%. Although its performance trailed behind the Nasdaq Biotechnology Index (up 3.74%) and the Dow Jones Industrial Average (up 13.7%), BDDI nonetheless made a recovery from the end of October when it was down 31.4%. Notably, the top two performers on BDDI in 2023 had stock rises attributed to approvals in rare disorders. In 2022, the index concluded the year down 20.13%, and in 2021 BDDI was up 7.06% at year-end.