It’s a myth that statisticians are obsessed with averages. We learn most from examining variability and the current concern with variants hammers home the importance of local data. Across the United Kingdom, confirmed cases of Covid-19 are stable, at 22 per 100,000 people in the week up to 17 May. Six local authorities recorded less than two cases per 100,000; while in Bolton there were 385 per 100,000, over 17 times the national rate. The excellent Public Health England dashboard provides even more granular data, down to the snappily named “middle-layer super output areas” (MSOAs) containing around 5,000 to 10,000 people. Three Bolton MSOAs had more than 1,000 per 100,000 (more than 1%) testing positive in that week, while other areas just a couple of miles away had fewer than 50 cases per 100,000. Much of this variation is likely due to the rise of the Indian variant B.1.617.2. Cases are concentrated in younger people, who are less vaccinated but more resilient; 84% of over-40s in Bolton have been vaccinated up to 16 May, using the National Immunisation Management System population numbers. This is like the England-wide average, but, again, masks local differences. The pattern of causation is complex, since similar factors, such as deprivation, ethnicity and multigenerational households, are linked to both the spread of the virus and vaccine uptake. Older white people hardly ever live with their grandchildren: of white households containing someone over 70, only 1.5% contain children and other adults, but this compares with 35% of Pakistani and 56% of Bangladeshi households that have someone over 70. As the national epidemic subsides, attention will move to local outbreaks, supporting intense local health responses such as extra testing and Bolton and elsewhere. It is vital that local data is publicly available and this is also true for economic statistics. There are now GDP measures in English regions to counter claims that national averages distract from local concerns - as one heckler in Newcastle notoriously put it: “That’s your bloody GDP. Not ours.” Statistics are for everyone and we all have a right to know what is going on around us. David Spiegelhalter is chair of the Winton Centre for Risk and Evidence Communication at Cambridge. Anthony Masters is statistical ambassador for the Royal Statistical Society