How to stateCount all tag data in one panel, one tag one stateCount time series?

measuremet like this: _time tag=err_code field=errCode
data:
t1 err_code=1 errCode = 1
t2 err_code=2 errCode = 2
t3 err_code=1 errCode = 1
t4 err_code=2 errCode = 2

How to stateCount all tag data in one panel, one tag one stateCount time series.

result like this: