I first wrote about this in post #10 ("Unpopular Leaders"). At the time, April 2013, I wrote the following (with [bracketed] explanations added), information I'd gotten from the newspaper:
Presidential Approval After One Month in Office [according to the Korea Herald]
% Approval.................President...............Year
..........71%.................Kim Young-Sam.......1993 [centrist; first non-military president since 1961]
..........71%.................Kim Dae-Jung.............1998 [left-wing; began Sunshine Policy with NK]
..........60%................Roh Moo-Hyun........2003 [left-wing; elected during anti-U.S. hysteria of 2002]
..........52%................Lee Myung-Bak.........2008 [right-wing freemarket type]
..........41%.................Park Geun-Hye..........2013 [right-wing, daughter of 1960s-1970s strongman General Park]
[O]ne cannot help think that Koreans are getting more and more cynical about their leaders, as time goes on.