Самое простое разрешение: df.stack
:
df = pd.DataFrame({'MIC-m': [138, 3, 22, 45],
'MIC-t': [34, 90, 30, 53],
'MIC-q': [73, 13, 53, 68],
'Total': [229, 229, 229, 229]}, index=['H', 'L', 'M', 'X'])
# Drop total, because we need sum of columns, not rows
df.drop(columns='Total', inplace=True)
# Get final result
df = pd.DataFrame(df.append(df.sum().rename('Total')).T.stack(), columns=['count'])
Выход:
count
MIC-m H 138
L 3
M 22
X 45
Total 208
MIC-t H 34
L 90
M 30
X 53
Total 207
MIC-q H 73
L 13
M 53
X 68
Total 207