Call:
lm(formula = f, data = d)

Residuals:
    Min      1Q  Median      3Q     Max 
-8.7004 -2.6329 -0.6432  3.1700 12.7231 

Coefficients:
            Estimate Std. Error t value Pr(>|t|)    
(Intercept)   7.9123     6.3944   1.237    0.223    
gdp           3.6412     0.7453   4.885 1.41e-05 ***
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1

Residual standard error: 4.322 on 44 degrees of freedom
Multiple R-squared:  0.3517,	Adjusted R-squared:  0.3369 
F-statistic: 23.87 on 1 and 44 DF,  p-value: 1.407e-05