I have an array:

```
const test = [1,2,2,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20];

```

I want to group the elements of the array into chunks of size 3 (quarters) and size 12 (years):

```
const quarters = [[1,2,2],[4,5,6],[7,8,9],[10,11,12],[13,14,15],[16,17,18],[19,20]];
const years = [[1,2,2,4,5,6,7,8,9,10,11,12],[13,14,15,16,17,18,19,20]];

```

I also want to compute the sum of each chunk:

```
const quarterSums = [5,15,24,33,42,51,39];
const yearSums = [77,132];

```

How do I do so?