The MRT system was hit by a series of serious disruptions in the 2010s, the most serious cases occurring in December 2011, July 2015 and October 2017. To address the problems, the government has sought to renew and expand the network as well as expand the workforce in the rail industry. This has included replacement of sleepers, third rail, power supply, signalling and track circuits on the North South and East West MRT Lines, procurement of new rolling stock for existing lines and building of new lines to relieve congestion on the existing lines. The Singapore Rail Academy was also inaugurated in 2017 to better train railway engineers and a new integrated train testing centre is to be built by 2022 to rigorously test new rail technologies. These efforts are starting to pay off with the reliability of the MRT lines improving by almost ten-fold by 2019.