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| InputDate | DayName | FirstWeekday |
|---|---|---|
| 2016-01-08 | Sunday | 2016-01-03 |
| 2017-05-05 | Sunday | 2017-01-01 |
| 2018-04-05 | Sunday | 2017-12-31 |
| 2019-03-03 | Sunday | 2018-12-30 |
| 2020-04-03 | Sunday | 2019-12-29 |
| 2021-05-06 | Sunday | 2021-01-03 |
| InputDate | DayName | FirstWeekday |
|---|---|---|
| 2016-01-08 | Monday | 2016-01-04 |
| 2017-05-05 | Monday | 2017-01-02 |
| 2018-04-05 | Monday | 2018-01-01 |
| 2019-03-03 | Monday | 2018-12-31 |
| 2020-04-03 | Monday | 2019-12-30 |
| 2021-05-06 | Monday | 2021-01-04 |