Clarke's was a small brewery in Stockport, taken over and closed by Boddingtons in the early 1960s. One of their brewing books survives. It handily includes costs. This is for their Bitter:
Here are those details in handy table form:
|Costs of Clarke 1/5 BB per brew (71.25 barrels)|
|Clarke brewing record held at Manchester Central Library, document number M693/405/137.|
The tax was more than five times the material costs. With such a high percentage of the cost of producing beer fixed in the form of tax, it didn't leave breweries much leeway to compete on price. Except in one way: by getting as much untaxed beer as possible.
A brewery could achieve that two ways. The first was to minimise losses during brewing. Tax was calculated on the volume and OG of wort as it went into the fermenter. There was an allowance of 6% for losses during brewing. A large, efficient brewery could reduce losses to quite a bit less than that. In the example above, 74.64 barrels were brewed and 71.25 were racked, which is a loss of 4.5%. Which means they paid no tax on just over one barrel.
The second way was dogier. That was to reuse stuff which had paid no tax. Such as returned beer, for which brewers received the tax back. Watney were particularly keen on this, using 15% "reprocessed beer" in most of their products.
Here's a breakdown of the costs per pint:
|Costs of Clarke 1/5 BB per pint|
40% of the retail price was tax. That's a pretty hefty chunk. Brewers were resentful of the fact that the governemnt earned considerably more per pint than they did themselves.