Mining roi increasing.......!!!!!

The crypto currency mining is going to the peaks and the hardware is going on advancing
At first they used computers and mined easily then due to difficulty they are upgraded to

After some days they are also not able to generate and the generation os asic has been started

The latest of the asics is s9 but till last month it had generated handsome revenue but as the difficulty goes on increasing the payouts of s9 are also dropping . And the roi is increasing .

Beside this their is gpu mining for which roi is 3 months but from past month it has also increased to 7-8 months as the prices of ethereum, and other currencies are going down so the best is we can go with litecoin miner
Model- antminer l3+