Have a button driving which metric is displayed in the line chart. 1st measure is dollar formatted with 2 decimal places. 2nd measure is whole number with no decimal places. The value labels on the chart adjust but the y-axis stays dollars.
1st master item expression
num(sum([Order Amount]), '$#,##0.00', '.' , ',' )
2nd master item expression
num(count(distinct [Order Number]), '#,##0', '.' , ',' )
Button Metric 1 measure is master measure with Num( [Gross Sales Price]), '$#,##0.##', '.' , ',' )
Button metric 1 measure is master measure with num(count([Order Number]), '#,##0', '.' , ',' )