bjcc raises a good question about beer compared to wine. British ale strength varies - draught bitters (the ones I drink) range from 3.3% to 5.5% ABV, though bottled beers can be much stronger than that, some almost as strong as wine.
Taking 4% as a round figure, a pint (568ml) will contain 23ml of alcohol (2.3 'units'), so a bottle of wine is roughly equivalent to 4 pints.
I'll get me anorak ...