。
This is that roughly allocated out to each stage of the process.
Literal
That [obj-を] roughly-[adverb-と] each stage [to-に] allocate-did thing [copula-です].
ざっくりと 'roughly / broadly' is a mimetic-adverb for approximate action — contrasting with きっちり 'exactly / precisely.' 割り振る 'to allocate / distribute among' is a compound verb (割る + 振る). ~ものです (attached here as ~割り振ったものです) is used to mean '(this is) what you get when you X,' presenting the current result as the product of the preceding action — typical of project-writeup style.