For me, if I can leave a few on top;
1/3 will be too shallow, will need a rain.
1/3 will be too deep, will not come up if it rains.
1/3 are just right, will come up with or with out a rain.

Drop 140,000; 10% will not germ, says so on the bag.
2/3 will come up, producing 84,000 healthy soybean plants.

Exactly what is needed for 99% of max yield.

Do not try this with naked seed.