Call:
lm(formula = y ~ x)

Residuals:
     Min       1Q   Median       3Q      Max 
-0.03053 -0.02248 -0.01435  0.01031  0.18290 

Coefficients:
                       Estimate Std. Error t value            Pr(>|t|)    
(Intercept)           0.0226982  0.0019277  11.775 <0.0000000000000002 ***
xLow income          -0.0061176  0.0043391  -1.410              0.1590    
xLower middle income -0.0003492  0.0034891  -0.100              0.9203    
xNA                   0.0041911  0.0066478   0.630              0.5286    
xUpper middle income  0.0078323  0.0032222   2.431              0.0153 *  
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1

Residual standard error: 0.03367 on 707 degrees of freedom
Multiple R-squared:  0.01535,	Adjusted R-squared:  0.009782 
F-statistic: 2.756 on 4 and 707 DF,  p-value: 0.02708