In the previous subsection it was mentioned that there are two types of thresholds of exclusion. Our attention then moved to the one set artificially, by law (legal threshold). But this is only the first threshold of exclusion. The second one is the so-called natural (or hidden, or effective, or informal) threshold. This one is present in any electoral system, regardless of whether or not the system also has any legal threshold. Even when there is no legal threshold at all, small parties can thus still face considerable natural thresholds for access to parliament. The natural threshold is the percentage of votes needed to get one seat at a district level, and is mainly dependent on the mean district magnitude (the average number of legislators returned per district, spanning from one in the UK to 150 in the Netherlands. The other factors affecting the natural threshold (but with a much less force than the first) are, the seat allocation formula (d’Hondt, Saint-Laguë, LR-Droop, Hare), the number of contestant political parties, and size of an assembly. Generally speaking, a system with small district magnitudes thus requires a relatively high percentage of votes per district to return a legislator. Conversely, the more seats there are to fill in the districts, the lower its natural threshold