Thanks. I appreciate the import of your question about walk-in use but it's essential to distinguish between what people *do* - borrow books and other things, read a paper etc and *what they are doing it for* - learning, work, fun. Function v. purpose.

Most people *do* more than one thing on a visit. In the Birmingham user surveys I recall, albeit a while ago, we asked people to tick off from a list of options. Most people ticked more than one. The ticks for 'Browsing' indicated that many people speculated and searched as well as coming to fulfil a particular need.

When looking at this, think of children too and young people. Their activity is diverse (eg play, socialising, homework and hobbies) and varies every couple of years through their age range depending on needs, wants and interests at the time. 

Also remember remote access and online use. This may still be relatively modest as, for example, there's low awareness of services such as Reference Online resources, Ancestry.co.uk and so on.

There is, of course, the burgeoning phenomenon of social media. No longer in fact a phenomenon; it's the norm and libraries must get in there now, creatively and promptly. It might help to respond to this survey for a take on the current connect between public libraries and social media https://www.surveymonkey.com/s/VSGGXBB 

Variations too across social settings: a librarian working in south coast towns told me most people really just want to borrow some books. In contrast, in Glasgow the library partners with Macmillan to provide information and support to cancer sufferers and their families. Surely this would be transferable to the retiree communities on the south coast.

Usage will also vary according to the scale of the provision. A core city central library with legacy collections, historic resources, archives, business information expertise, unique music collections - none of which could be provided (physically) in every local library - will experience a huge diversity of needs and expectations among their visitors. 

Ultimately a library is a service of choice; the visitor determines the service. Without regular and frequent  monitoring alongside surveys and longitudinal research it's not easy to forward plan for service development and delivery.

This is why your question as well as being important, reflects a specific and ongoing need. Meanwhile ACE's research into the economic contribution of public libraries will offer a valuable retrospective analysis and, surely, inform further innovation.

A wide understanding of the society in which we live (see CILIP's Professional Knowledge and Skills Base) tells us about the context in which we work and what library provision we *should* be making to meet today's economic and social needs. 

I hope this is of interest if not of value. A shorter response might have said, See:

http://www.cipfasocialresearch.net/libraries/plus/ and stuff from LISU. I expect others will be familiar with further sources of help they can contribute. 

John