Updating Threshold Data without losing History

Hello!

I have a table which contains daily orders by item, by location, by date.  I have another table which counts the # of lines of the daily orders along with the total cost of those orders at the date level . 

I have a threshold that says if the daily total # of lines and/or total cost $ is under this line/cost threshold check a checkbox​​.  This checkbox is then used to note an "over/under" in a grid edit report where details can be entered as to why a particular day is over/under for lines or cost. 

We are updating our thresholds today and I need a way that I can update my thresholds with the new threshold information but anything prior to today would remain at the previous threshold levels so as not to lose any historical information.  I would only want the new threshold information to be used from today forward.  Is there a way to accomplish this? 

I have created another table with a start and end date (which is currently not being used) but didn't know if there was a way to utilize this to do what I'm trying to do.  I hope this all makes sense.

Thank you for any guidance!

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Laura Beverley
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