find the count of each date in dataframe

I need to group the columns according to the date.

starttime   Dates   COUNT
0   2019-09-01 00:00:01.9580    2019-09-01  0
1   2019-09-01 00:00:04.1430    2019-09-01  0
2   2019-09-01 00:00:07.3090    2019-09-01  0
3   2019-09-01 00:00:08.0640    2019-09-01  0
4   2019-09-01 00:00:12.8510    2019-09-01  0
... ... ... ...
195 2019-09-01 00:08:17.9740    2019-09-01  0
196 2019-09-01 00:08:23.9270    2019-09-01  0
197 2019-09-01 00:08:25.5040    2019-09-01  0
198 2019-09-01 00:08:26.2810    2019-09-01  0
199 2019-09-01 00:08:27.3220    2019-09-01  0

I have used the below to split my ‘starttime’ column to just the Date and Time. I want to count the number of occurences of each date in ‘COUNT column.

df['Dates'] = pd.to_datetime(df['starttime']).dt.date
df['Time'] = pd.to_datetime(df['starttime']).dt.time

For example

Date       COUNT
2019-09-01    25
2019-09-02    34

How can i do this?

>Solution :

Try this :

output = df.Dates.value_counts().reset_index()
output.columns = ["Date", "Count"]