SQL: QUERY, IF Statement

I've got the following table with 3 columns

date_actual	vehicle_ID	Parked
2021-06-27	1234	0
2021-06-28	1234	0
2021-06-29	1234	0
2021-06-30	1234	1
2021-07-01	1234	1
2021-07-02	1234	1
2021-07-03	1234	1
2021-07-04	1234	1
2021-07-05	1234	0
2021-07-06	1234	0
2021-07-07	1234	0
2021-06-27	5555	0
2021-06-28	5555	1

Basically a table containing dates, vehicle_ID's and a third column that tells whether or not a car was in a compound (Parked). I need create a fourth column to this table called: Inflow. Inflow needs to give me the following output:

If a car is parked on date x, but was not parked on date x - 1, it should have inflow = 1 If the first date of a car that is available in the table already starts with a 1, inflow should be 0. Hope you guys can help me out.

I tried:

select t.*,
(case when coalesce(lag(Parked) over (partition by vehicle_ID order by date_actual), parked) = parked - 1
then 'true' else 'false'
end) as inflow from t;

With kind regards,

Lazzanova