https://www.pcgamer.com/ram-prices-are-finally-cheap-again/

Back in 2016, you could get 16GB of DDR4 RAM for around $70, but the increasing demand from mobile phones using DDR4 chips, followed by some setbacks in production drove prices up throughout 2017. The cost of that same 16GB kit peaked around $200 in early 2018. 

Thankfully there was relief in sight. In late 2018, DRAMeXchange said that falling demand for DRAM at various levels—a combination of sluggish smartphone sales and lower PC and laptop production due to the shortage of Intel CPUs—would lead to lower DRAM prices in 2019 as well. Sure enough, we're finally starting to see memory available at much closer to those pre-shortage prices.