For all time intervals (hourly, daily, weekly, monthly), CloudHealth runs calculations based on what is present in the AWS billing file at that moment. Unfortunately, the AWS billing file is only an estimate until the end of the month.
According to AWS:
“During the current billing period (monthly), AWS generates estimated billing reports. The billing reports are not bills, but estimates of costs and charges for AWS usage. Only the monthly invoice you receive each month contains your actual charges.”
Due to this method used by AWS, even after a day or week has concluded, AWS may post adjustments to cost and usage for that time period up until the final invoice from AWS is completed, which is usually by Day 5 of the following month. This delay can result in apparent discrepancies when comparing your reports for the current month (hours, days, weeks, or current month) at different times during the month.
Official invoices may be sent out prior to finalized billing files posting at the beginning of the month so there could be a short period of time where the invoice does not reflect the CloudHealth reporting. They usually sync up within a few days and the finalized billing data will be present in the platform.