Liquids and solids are hard to compress, so elements in gaseous state will be the clear winners.  On the other hand gases satisfy quite well the equation of state of an ideal gas, thus they all behave practically in the same way, no matter which one you select.  Interestingly d(density)/d(pressure) = const/T   (at T fixed). where const is the same (universal) for all gases.

For all ideal gases, to be precise - if you have to use Van-der-Waals equation that won't work any more because the co-volume and the cohesion pressure are gas dependent.

For all ideal gases, to be precise - if you have to use Van-der-Waals equation that won't work any more because the co-volume and the cohesion pressure are gas dependent.

In solid Cerium, you can induce the isostructural gamma-to-alpha Cerium transition by applying pressure. This goes along with a volume contraction of about 15%.