Great Depression
From Tardis Wiki, the free Doctor Who reference
The Great Depression was a worldwide economic downturn which began in 1929 and lasted for over a decade (only totally ending in 1941 when the US joined the war).
The Tenth Doctor and Martha Jones visited New York City during the Great Depression and witnessed the poverty it generated when they visited a Hooverville in Central Park. (DW: Daleks in Manhattan / Evolution of the Daleks)
