Call:
lm(formula = sales ~ t, data = salesdw)

Residuals:
     Min       1Q   Median       3Q      Max 
-10.0010  -4.7013  -0.3879   2.5012  15.8771 

Coefficients:
            Estimate Std. Error t value Pr(>|t|)    
(Intercept)   0.4015     2.2057   0.182    0.857    
t             4.2956     0.1069  40.196   <2e-16 ***
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1

Residual standard error: 6.385 on 33 degrees of freedom
Multiple R-squared:   0.98,     Adjusted R-squared:  0.9794 
F-statistic:  1616 on 1 and 33 DF,  p-value: < 2.2e-16

 lag Autocorrelation D-W Statistic p-value
   1       0.5896241     0.8207268       0
 Alternative hypothesis: rho != 0