Mark key dates in area chart

Hi, TomJWhite 

You can create a column and use it in legend, and note that It’s best not to have the same name, or it will connect.

Like this:

Main Date = 
SWITCH (
    TRUE (),
    'Table'[Date] = DATE ( 2021, 3, 23 ), "First Lockdown begins",
    'Table'[Date] = DATE ( 2021, 5, 13 ), "Move to Level 2",
    'Table'[Date] = DATE ( 2021, 6, 9 ), "Move to Level 1",
    'Table'[Date] = DATE ( 2021, 8, 30 ), "Move to Level 2 again",
    'Table'[Date] = DATE ( 2021, 8, 12 ), "Second Lockdown begins",
    " "
)

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Best Regards,

Community Support Team _ Janey