(2) The board shall adopt rules establishing benefits and service credit for any period of service in the uniformed services by an employee described in subsection (1) of this section. For the purpose of adopting rules under this subsection, the board shall consider and take into account all federal law relating to benefits and service credit for any period of service in the uniformed services, including 26 U.S.C. 414(u), as in effect on December 31, 2018. Benefits and service credit under rules adopted by the board pursuant to this subsection may not exceed benefits and service credit required under federal law for periods of service in the uniformed services. [2003 c.733 §13; 2009 c.5 §3; 2009 c.909 §3; 2010 c.82 §3; 2011 c.7 §3; 2012 c.31 §3; 2013 c.377 §3; 2014 c.52 §3; 2015 c.442 §3; 2016 c.33 §4; 2017 c.527 §4; 2018 c.101 §4; 2019 c.319 §4]