Figures from the ONS: 
Lowest ten per cent   6,760 
Second decile group   13,000
Third decile group   17,680
Fourth decile group   22,880
Fifth decile group   28,600
Sixth decile group   34,840
Seventh decile group 42,640
Eighth decile group   52,520
Ninth decile group   66,560
Highest ten per cent   118,560
So if your profit is £28,600, half of all people are earning more than you, half less.
If your profit is £17,680, seven out of ten people earn more than you, three out of ten less.
Data from 2016. Doesn't include retired people. And it's gross household income so includes your other half's earnings (if any) and your other job as a fireman.
Vin