District of Columbia is about 1,008 times smaller than Missouri.

Missouri is approximately 178,414 sq km, while District of Columbia is approximately 177 sq km, making District of Columbia 0.1% the size of Missouri. Meanwhile, the population of Missouri is ~6.0 million people (5.4 million fewer people live in District of Columbia).
Tip: This to-scale comparison of Missouri vs. District of Columbia uses the Mercator projection, which distorts the size of regions near the poles.