Reference texts (dictionaries, cookbooks, parts catalogues/specification data books) aren't really things I'd 'read' like a novel or an essay. I might browse a cookbook for ideas, but most of the time I'm looking up a specific technique or recipe. It's not read, it's not unread, it's not 'unfinished'. Perhaps we could have a status for texts primarily consumed in nonlinear ways? Or a way to create our own statuses?