The first digit after the decimal is the tenths place, then the hundredths, then the thousandths. It's reverse of the other direction, but there is no oneths place.
0.019 = 19/1000
One way to remember is that dividing by multiples of 10 moves the decimal left as many times as there are zeroes.
19/10 = 1.9
19/100 = 0.19
19/1000 = 0.019
19/10,000 = 0.0019
and so on