We're right in the middle of the summer holiday season in the UK and people are starting to take their well-deserved annual breaks.
It poses a tricky problem for some teams because the capacity and skill set of the team vary drastically from sprint to sprint and even mid-sprint. When that happens you'll want to pay close attention to how the team is doing against the sprint backlog. All else being equal, that's the job of the burndown chart.
The trouble is, it doesn't handle this situation very elegantly at all because it assumes even capacity and that isn't always the case.
The Situation : Uneven Capacity
Sometimes, you'll have a sprint where everyone is in the office in the first half, and a lot of people are off in the second half (or something similar). So, you'll take on less work for that sprint based on your knowledge of velocity or throughput. In the first week (I'm assuming 2-week sprints), you get loads done and the burndown shows you might finish early. You know that's unlikely because the second week is going to be a ghost town but you're not sure how much it's going to affect you.
That's pretty crappy situation really and you can end up getting burndowns that look like this...
The second week goes practically untracked because the ideal line is wrong! It also doesn't show how much less expertise the team have access to so it's common to see work take a bit longer than it would if everyone was in the office.
It's really easy to lose focus when this happens. People quickly become stressed and you under up under delivering as a result. Not good for anyone.
The Solution : Track Holidays as Work
The solution is really straight-forward and I recommend it to all but the most mature of teams. Firstly, plan and track your sprint backlog in hours.
I know some people disagree with me on this and I understand why. Tracking time doesn't measure progress towards done. You should burndown in story points (or whatever) too or limit WIP to avoid everything being 90% done at the end of the sprint . Ultimately though, you are planning the execution of a (probably) two-week plan and time is the constraint in a time-box. So, plan for it!
When you've got that, simply add another story or epic (or whatever you might use) to the board to represent holiday time. You can bulk all the non-development time into one big bucket if that makes sense in your situation.
Each day, move the holiday tickets across the board like you would any other kind of work. You can think of them as freebies.
What that does is adjust your actual progress against the ideal so it's they're still relative to each other.
This idea scales just as easily to release burndowns too. Give it a go and let me know what you think.