FOI ref: FOI-2024-2171

You asked

In the section on mobile phone chars, the CPI technical manual states:

"Profiles are categorised according to voice and text usage and, from 2011, data usage. Company indices are further subdivided between pay-as-you-go (PAYG), contract customers and SIM-only customers, with some variation in specific methodology employed in each case, as we will describe next. The final index is a weighted average of the company indices, with weights based on expenditure shares supplied by OFCOM."

Please can you share an all company-aggregated weight for contract/sim-only/PAYG?

Please can you also share an 'average price' for each in the latest CPI?

We said

Thank you for your query about the mobile phone charges component of consumer price inflation.

The all company aggregated weights for contract, SIM only and pay-as-you-go are approximately 43%, 40% and 17% respectively.

We do not calculate an overall average price for contract, SIM only and pay-as-you-go for the latest CPI. Therefore, this information is not held. The range of prices for an item such as mobile phone charges can be large. As a result, any average price would be highly variable depending on the sample taken and, as such, largely meaningless.

The indices are designed to measure price change based on a fixed basket, not absolute price levels, and so the individual prices are converted into price relatives by comparing the latest month with the equivalent January prices before any aggregation is carried out. Thus, all aggregates are expressed as index numbers, not as average prices.