Day Over Day Variance for Week

I am working on a report that I need to show a day over day variance for a 7 day week. I already have a variance Chart to show week over week which I have found on another topic. I have tried to use that same method for the day over day variance, but I am not getting what I am looking for.

Example

I get the daily totals correct, but the variance usually shows up 0 which I do not believe is right.

Daily Variance = var lastDayAmount = CALCULATE(sum(AS400[Y1NWGT]), filter(all('AS400'), 'AS400'[Weekday #]=min(AS400[Weekday #])-1)) return DIVIDE(sum('AS400'[Y1NWGT])-lastDayAmount,lastDayAmount,0)

I tired: 

Variance = var lastWeekAmount = CALCULATE(sum(AS400[Y1NWGT]), filter(all('AS400'), 'AS400'[Week Number]=MIN(AS400[Week Number])-1)) return DIVIDE(sum(AS400[Y1NWGT])-lastWeekAmount,lastWeekAmount,0)

 

And got: 

 

Use Weekly Variance

 

The percentages are off. They all show negative.