SQL Query - Return Operation Over Multiple Dates

I am new to SQL and I am just wondering if there is a solution to a problem I am having.I am using the piece of code below.Essentially what I am doing is selecting a field from a table and ordering that field in descending order. Using the Row_Number feature I then specify which Row I want to return.

Every day the row I will want is the Count of field1 for that day divided by 100 minus 1. This returns a single value of field1 and a single value of R.

I perform this operation every day. The only fields I change every day are the dates and the value of R. I use a seperate piece of SQL code to calculate R each day.

My problem is I have to often populate historical tables with this data. I can only run the code once for each day and for each value of R. Is there anyway I can alter this code such that it can return multiple values of field1 over several dates?The only way I can think of is to repeat the code multiple times using UNION but I am hoping there is a more efficient way.

SELECT *
FROM (SELECT Field1,
ROW_NUMBER() OVER (ORDER BY field1 desc ) R
FROM table
WHERE date >= TO_DATE ('20110215', 'YYYYMMDD')
AND date < TO_DATE ('20110216', 'YYYYMMDD')
)
WHERE R = 1227
--Note: 1227 = (count(field1)/100)-1