I think you are asking for the number of sales per sales person from a given
Having a column whose data type is date enables you to use logical operators
like <, >, <=, >= and = and not have to break up the date into parts.
select sales_person_id, count(sales_person_id) as 'Total Lots' from
sales_table where start >= '1/1/2004' group by sales_person_id
if you need the total for a month then add an extra condition to the where
clause. Example where for the month of january 2004, use start >= '1/1/2004'
and start < '2/1/2004'