Uranus follows an elliptical orbit around the sun that takes 84.3 Earth years to complete. The length of a planet's year is determined by its distance from the sun. Uranus travels at an average distance from the sun of just over 19 times that of Earth.
Kepler's Third Law states that the square of a planet's orbital period is proportional to the cube of the semi-major axis of its orbit. This means that every planet, regardless of its size or composition, goes around the sun at a velocity determined by its distance. Earth is, by definition, 1 AU away from the sun and takes 365 days to complete one orbit. Mercury is at 0.4 AU and has a year that lasts 88 days. In each case, the ratio between distance and length of year remains constant.