What percent of shamrocks actually turn out to be 4-Leaved Clovers. Also, where is the best place to find them

Just curious, because it's Spring time.

What percent of shamrocks actually turn out to be 4-Leaved Clovers. Also, where is the best place to find them
The Irish shamrock is thought by many authorities to be white clover (Trifolium repens), which has mostly leaves with three leaflets. Botanically, a four leaf clover is actually a four leaflet clover because it is a single leaf with four leaflets. Several companies sell four leaf clovers as lucky charms or cover them with gold to make jewelry. Park Seed Company sells plants of a Red Four-Leaf Clover (Triflorum repens 'Atropurpureum'). Another company sells seeds of a four leaf clover with up to 39% of the leaves with four leaflets.