Attributed in part to poor weather, the data showed average drinks sales by value in managed sites were 3% down in the seven days to Saturday 22 July compared with the same period in 2022.
It marked the second week in the red for the sector, after a 0.3% drop in the previous seven days, which followed 11 consecutive weeks of year-on-year growth.
The figures demonstrated the worst performance for the on premise since late April, CGA added.
CGA managing director UK and Ireland Johnathan Jones said: “After 11 consecutive weeks of year-on-year growth, it is disappointing to see the tracker showing decline in the latest week.
“However, with the context of rail strikes and much poorer weather than last year, we shouldn’t be viewing this week in isolation as a barometer for the health of the sector.
“Our research shows that consumers, particularly the core on premise visitor, are still keen to come out into the trade and are prioritising eating and drinking out above other discretionary spending.”
In addition, CGA stated the week suffered “tough comparatives” with the heatwave of July 2022 on top of rail strikes, which reduced footfall in some cities and towns, with sales down 5% and 7% on Thursday and Saturday, the two main strike days, vs last year.
The data also indicated a “wide fluctuation” in daily sales across the week, from a low on Monday (down 13%) to highs of 6% on Wednesday and Friday.
Category wise, wine sales were 13% ahead year-on-year as consumers turned away from beer gardens and towards food-led occasions, while cider sales dropped 19% as drinkers headed indoors.
Beer achieved modest 1% growth, while soft drinks and the spirits category were down 4% 13% respectively, the worst week since April for spirits.
Jones added: “With the majority still telling us that this is the main way they socialise with others.
“So, whilst we will all be hoping for brighter weather and an end to transport disruptions, we shouldn’t be too concerned by this short-term dip in performance.”