The cost of living crisis has seen the prices of many goods and services rise sharply in the past 18 months, but food and drink prices have been particularly hard hit.

Some food producers have responded by reducing the size of their products, while keeping prices the same – a phenomenon known as “shrinkflation”.

When several major brewers were reported to have reduced the strength of beers recently, including Fosters lager (cut from 4% alcohol by volume (ABV) to to 3.7%) and ales such as Old Speckled Hen and Spitfire, it led to accusations of “drinkflation” and short-changing of customers.

Duty on beer is levied on the basis of alcohol content, so a 0.3% reduction in ABV equates to a saving of around 4p on a pint. Brewers can pocket this if they keep the sales price the same. If this seems like small beer, consider the fact that we drink around 7.8 billion pints each year in the UK, meaning that a 0.3% cut across all beers would see industry revenue rise by £290 million a year.

Brewers and the British Beer and Pub Association have pointed to rising production costs and squeezed profit margins as the justification for these reductions in strength. But concerns remain that the great British pint is becoming another casualty of the cost of living crisis.

But this is not a new phenomenon. Brewers have been cutting the strength of major beer brands for well over a decade. In many cases this is done with minimal publicity and without many consumers even noticing.

HMRC collects alcohol taxes on behalf of the UK Treasury and requires all alcoholic products above 1.2% to advertise their alcoholic strength on the label. But beer producers are allowed a little wiggle room around this, provided the value on the label is within 0.5% of the true strength.

This is a concession to small producers who may find it hard to produce every batch to exactly the same ABV but don’t want to have to produce new labels with each small variation.