Count number of sends per brand

Is it possible to count the number of sends (campaigns, autoresponders, drips) sent per brand, per period of time (ie, per calendar month, per week, etc)?

I can probably hack this in going forwards, but is there a way to get this information historically?

Any pointers for when I come to add this code myself? I know PHP, but not at the level that Sendy is written!

Thanks.