Korean language and Chinese language have become significant since the 1970s.
The surge in discouraged workers is the most significant since the months immediately after the recession's start.
The 1970 restructuring of the school system, the most significant since the turn of the century, created a unique hybrid.
Electricity has been significant for the economy and politics since the late 19th century.
The difference of about two years is significant since, as I understand it, an application lapses if not implemented within a certain time.
The rule changes are the most significant since the restriction of hand-checking by defensive players before the 1994-95 season.
The area has been religiously significant since ancient times.
The moves are regarded as the most significant since the late 1960's and early 1970's.
The move is highly significant since Britain's fleet and business market accounts for around two-thirds of total car sales.
The surge in discouraged workers is the most significant since the months after the Sept. 11 attacks.