Support uneven budgeting

To accomodate this, one way would be to have an extra scheduling field for budget called "Duration" (with a default to "the whole scheduled period"). For example, if you want a budget that only spans in the summer, you would create a yearly budget that starts at the beginning of the summer, but with a duration of only 4 months (rather than the whole year).

To have monthly budgets that have a different value every month, it would be a little more complicated to set up, but it would still be possible. You could create 12 yearly budgets with 12 different values and start dates, and each of them would span only one month.