Money Stock market: Here’s why your 401(k) is celebrating 2019 before ringing in 2020 December 31, 2019December 31, 2019 Jessica Menton, USA TODAY Comments Off on Stock market: Here’s why your 401(k) is celebrating 2019 before ringing in 2020 The longest-ever bull market is headed toward an 11th year. Those who sat on the sidelines in 2019 following last year's tumult lost out on big gains.