get percentage by multiple grouping

I have a dataset that looks like the following (the following is only the first few lines)

Rate Category Status Value

1.1 A 1 500

1.7 B 0 250

1.8 C 2 1075

.....

So Rate and Value both have numerical values. Range of Rate is -5 to 5. Category has values A,B, or C. Status only takes on values 0,1,2. I want to calculate the percentage of value for each rate bucket + category bucket + "status=1". I want to divide rate bucket into a 0.5 wide discretization, that is, (-inf,0.5],(0.5,1],.... and eventually have the following table:

Rate Category %_of_status = 1(in value)

<=0.5 A 10%

0.5-1.0 A 15%

.....

For example the first %_of_status in the table above should be calculated this way: take all values where rate<=0.5 and category = A and calculate sum(value,status = 1)/sum(value)

What is the fastest way to do this? Thanks.