Exactly!
I just did the test with two brionnes that I got from breeding, they have natures that doesn't affect their speed and their only difference in speed is the 25 Evs:
Their speed stat differ by 1, if you apply the formula: speed=(((((2*base+IV+(Ev/4))*lvl)/100)+5)*nature)
For B1: (((((2*50+31+(0/4))*24)/100)+5)*1) = 36.44
For B2:(((((2*50+31+(25/4))*24)/100)+5)*1) = 37.94
The stat is always rounded down if the result is a decimal.