When I use the RSQ function between one x variable and y variable, the resulting $R^2$ differs from the $R^2$ values given by running regression analysis from excel’s Data Analysis.

For example, here’s what I get from regression:

```
Multiple R 0.738117539
R Square 0.544817502
Adjusted R Square 0.479791431
```

And RSQ gives me a value of `0.6594`

.

Here’s the data:

```
Y:
56,324.0
72,347.0
95,803.3
92,903.7
104,859.9
127,584.9
131,030.9
137,358.6
129,092.2
135,803.4
X:
54.4
65.2
72.5
96.9
61.5
79.5
111.3
111.7
108.6
107.2
```

Which one is the most accurate out of these 4 values? What’s the difference? Also, why are there calculations for Multiple R and Adjusted R Square when I’ve only done a single variable regression (to my [very limited] understanding, those are for multi variable regressions); should those just be disregarded?

Thanks!