I have a table like this:

```
Values        Type       Year
1500          A          1
964           B          1
-222          B          2
761           A          2
2400          C          1
-100          A          1
144           B          2

```

My question is: how can I show the positive and negative values separately (creating 2 data frames named POsitive value and Negative value, in my opinion) and how to demonstrate netted values?

The expected output 1 is:

```
Data frame 1 (positive values):
Values        Type       Year
1500          A          1 
964           B          1
761           A          2
2400          C          1
144           B          2

Data frame 2 (negative values):
Values        Type       Year
-222          B          2
-100          A          1

```

Expected output 2 (netted values):

```
Values         Type      Year
1400           A         1
761            A         2
964            B         1
-78            B         2
2400           C         1

```