Null Count & Percentage

Andybr 

you can use Percent of grand total option in visuals or create a measure like

Measure = 
DIVIDE(
CALCULATE(COUNTROWS(Table), Table[Value] = "1234567"),
CALCULATE(COUNTROWS(Table), ALL(Table))
)

Hi Andybr ,

 check this.

Measure = DIVIDE(COUNTROWS(FILTER('Table','Table'[Column] = 1234567)),COUNTROWS('Table'))

https://docs.microsoft.com/en-us/dax/divide-function-dax

https://docs.microsoft.com/en-us/dax/countrows-function-dax

https://docs.microsoft.com/en-us/dax/filter-function-dax

Hi Andybr 

try this

Measure = 
DIVIDE(
COUNTROWS(Table),
CALCULATE(COUNTROWS(Table), ALL(Table))
)