Here is a quick SQL snippet to get Project Cost Rates based on effective date and company.
SELECT proj.costprice
FROM [AX_DATABASE].[dbo].[HCMWORKER] w
JOIN [AX_DATABASE].[dbo].[PROJHOURCOSTPRICE] proj ON w.recid = proj.worker
WHERE proj.transdate >= ‘1/1/2017’
AND proj.dataareaid = ‘CompanyName’