Oops, it doesn't look like 'average on the day' is a national day..

Other days

gum

Gum Day
hoodie

Hoodie Day
believe

Believe Day
martini

Martini Day
boba

Boba Day
kiss a ginger

Kiss A Ginger Day
kale

Kale Day
ormille

Ormille Day
kiss a brunette

Kiss A Brunette Day
lash

Lash Day