SQL Group by Transpose

I have the following Table charges

charges:
|Quantity|Timestamp| Charge|
|--------+---------+-------|
|       1|8/01/2020| Yearly|
|       2|8/01/2020|Monthly|
|       1|8/01/2020|Monthly|
|       2|8/02/2020| Yearly|
|       1|8/02/2020|Monthly|
|       1|8/02/2020|Monthly|

Using the following query gets my the counts by Charge and Date

Query:
select SUM(Quantity), Timestamp, Charge 
from charges 
group by Timestamp, Charge 

Result:
|Sum|Timestamp| Charge|
|---+---------+-------|
|  1|8/01/2020| Yearly|
|  3|8/01/2020|Monthly|
|  2|8/02/2020| Yearly|
|  2|8/02/2020|Monthly|

Is there a way to transpose this to get the following?

Expected:
|Timestamp|Yearly|Monthly|
|---------+------+-------|
|8/01/2020|     1|      3|
|8/02/2020|     2|      2|

Thank you.

Answer

Use conditional aggregation:

select
    timestamp,
    sum(case when charge = 'Yearly'  then charge else 0 end) yearly,
    sum(case when charge = 'Monthly' then charge else 0 end) monthly
from charges
group by timestamp