Mining Profitability of BTC and BCH
Source: fork.lol (PNG by me)

mining\space profitability$$\frac{\mathrm{BCH}}{\mathrm{BTC}}=\frac{\frac{(\mathrm {BCH\, block reward + estimated\, total\, transaction\, fees \, in \, a \, BCH \, block})\cdot (\mathrm {BCH\, exchange\, rate\, (in\, USD)})}{\mathrm {BCH\, block\, difficulty}}}{\frac{(\mathrm {BTC\, block reward + estimated\, total\, transaction\, fees \, in \, a \, BTC \, block})\cdot (\mathrm {BTC\, exchange\, rate\, (in\, USD)})}{\mathrm {BTC\, block\, difficulty}}}$$