Source: "The Management Theory Jungle," 1961, p. 174
Quotes about decade
page 4

Introduction to Capital. Introduction to volume 1 (1976)

Address By Dr. Shanker Dayal Sharma President Of India On The Occasion Of The 50th Anniversary Of The First Sitting Of The Constituent Assembly

“I love chess, but it's the height of decadence.”
The King's Gambit (2007)

“If we continue on for decades as before, then I have to be pessimistic about our country.”
in conversation with the authors of the series of documentaries "Der Fall Deutschland", statcion Phoenix, 12. February 2006, phoenix.de http://www.phoenix.de/24378.htm
Interview in Prospect Magazine http://www.prospect-magazine.co.uk/article_details.php?id=7950

Francis Boyer Lecture of The American Enterprise Institute for Public Policy Research, Washington, D.C., December 5, 1996 http://www.federalreserve.gov/boarddocs/speeches/1996/19961205.htm.
1990s

Source: Sex, Art and American Culture : New Essays (1992), Rape and Modern Sex War, p. 51

Two Bad Answers http://takimag.com/article/two_bad_answers_john_derbyshire/print#axzz33lq12wO9, Taki's Magazine, June 5, 2014.

6 October 1996 "Down With the Presidency" http://www.lewrockwell.com/rockwell/down-presidency.html
1990s

Von Foerster (1960) as cited in Peter M. Asaro (2007). "Heinz von Foerster and the Bio-Computing Movements of the 1960s," http://cybersophe.org/writing/Asaro%20HVF%26BCL.pdf
1960s

The Long, Painful History of Time http://naggum.no/lugm-time.html.
"Role Models" (p.202)
So This Is Depravity (1980)

2010s, 2016, July, (21 July 2016)

Destruction of Buddhist monuments in Afghanistan and the Babri Masjid http://www.pucl.org/reports/National/2001/buddhist.htm (2001)
Source: The Human Side of Enterprise (1960), p. 17 (2006: 24)

2010s, The Deflation of the Academic Brand (2018)
Spectrum: From Right to Left in the World of Ideas (2005), Ch 10. "Tropical Recall, Gabriel García Márquez" (2005)

Giles Whittell, " The world according to Richard Dawkins http://www.thetimes.co.uk/tto/science/article4191347.ece" (), The Times, quoted in Trevor Grundy, " Richard Dawkins Pedophilia Remarks Provoke Outrage http://www.huffingtonpost.com/2013/09/09/richard-dawkins-pedophilia_n_3895514.html" (), The Huffington Post.

1960s, Why I Am Opposed to the War in Vietnam (1967)

Why Apple is right to fight FBI over iPhone access http://cio.com/article/3035517/legal/why-apple-is-right-to-fight-fbi-over-iphone-access.html in CIO (19 February 2016)

2000s, 2008, Address to the United Nations General Assembly (September 2008)

"Have the Mullah's Abandoned their Dreams of Empire?", Elaph.com, (November 16, 2014).

“Progress of mankind is the decadence of humanity.”
page 15
The Other Wife (2003)

http://www.mikebloomberg.com/en/issues/education/mayor_bloomberg_announces_that_high_school_graduaton_rate_reaches_historic_high_of_60
Education
A Short History of the World (2000)

Quoted in "2009 Australia's second warmest year ever, according to Bureau of Meteorology figures" http://www.heraldsun.com.au/news/australias-second-warmest-year-ever-according-to-bureau-of-meteorology-figures/story-e6frf7jo-1225816322149 in the Herald Sun, January 5, 2010.
2010

Interview with Radio.com (July 6, 2016)

Speech by President Serzh Sargsyan in the Chatham House British Royal Institute of International Affairs http://www.president.am/events/news/eng/?search=Chatham+House&id=898 (February 10, 2010)
Alan Hovhaness, 1940 Guggenheim Application http://www.hovhaness.com/hovhaness-biography.html

Viktor Schauberger: Our Senseless Toil (1934)

Full transcript of bin Ladin's speech http://www.aljazeera.com/archive/2004/11/200849163336457223.html Aljazeera, (01 Nov 2004)
2000s, 2004

Mazurek, Maria (13 May 2016): Komórki rakowe to anarchizujące potwory https://gazetakrakowska.pl/komorki-rakowe-to-anarchizujace-potwory/ar/9985395. Gazeta Krakowska (in Polish), pp. 18–19.

Comedy specials, Deep in the Heart of Texas: Dave Chappelle Live at Austin City Limits (2017)

Definitions
This is Dinosaur: Echo Park Country and its Magic Rivers is a collection of essays and photographs edited by Wallace Stegner and published by Alfred A. Knopf in 1955. This passage is from the collection's first essay, "The Marks of Human Passage", which is by Stegner (page 17).

Superman Comes to the Supermarket (1960)

Presidential campaign (April 12, 2015 – 2016), Speech in Orlando, Florida (September 21, 2016)
Source: Information and Decision Processes (1960), p. viii

Source: The Singularity Is Near: When Humans Transcend Biology (2005), p. 329

U.S. president George Bush made those comments on January 1, 1990. The Watchtower magazine; In Search of a New World Order (15 July 1991)

2016, Remarks on Donald Trump and the 2016 race

New Brunswick Telegraph Journal, May 29, 2002.
2002

1990s, I Am a Man, a Black Man, an American (1998)

Tessa Virtue, Interview for Sportsnet.ca (January 2018)
Partnership with Tessa Virtue, Tessa Virtue about Moir
1960s
Source: 'A period of Exploration', McChesney, as quoted in The New York school – the painters & sculptors of the fifties, Irving Sandler, Harper & Row, Publishers, 1978, p 35

Audio lectures, Decadence and the New Age (March 10, 1989)

Anand Patwardhan, the Michael Moore of India -Interview UC Berkeley News http://berkeley.edu/news/media/releases/2004/10/13_patwardhan.shtml (October 13, 2004)

2000s, 2004, Speech to United Nations General Assembly (September 2004)

Sissy Diaries: The Harsh Realities of Dating for Gender-Nonconforming Femmes https://www.them.us/story/sissy-diaries-dating-while-nonbinary (April 25, 2018).

1960s, Why I Am Opposed to the War in Vietnam (1967)

[2008, http://www.edge.org/q2008/q08_5.html#baez, Should I be thinking about quantum gravity? (essay at the World Question Center), edge.org]

Speech http://hansard.millbanksystems.com/commons/1937/may/05/supply in the House of Commons (5 May 1937).
1937
Source: Piero Sraffa: His life, thought and cultural heritage (2000), Ch. 1. Piero Sraffa
George Katona, and James N. Morgan (1980). Essays on behavioral economics. Univ of Michigan Survey Research. p. 3

Article, October 19, 2009, "Decline is a Choice" http://www.weeklystandard.com/Content/Public/Articles/000/000/017/056lfnpr.asp at weeklystandard.com.
2000s, 2009

Do Books Matter? (ed. Brian Baumfield), ISBN 0705700143, p. 27.
Do Books Matter?
Hindu Society under Siege (1981, revised 1992)

Putin is turning the Syrian coast into another Crimea http://nypost.com/2015/09/19/putin-is-turning-the-syrian-coast-into-another-crimea/, New York Post (September 19, 2015).
New York Post

What the Fox News Bill O'Reilly fiasco teaches businesses http://cio.com/article/3193003/leadership-management/what-the-fox-news-bill-o-reilly-fiasco-teaches-businesses.html in CIO (28 April 2017)

At a memorial lecture for the late struggle icon Winnie Madikizela-Mandela in Johannesburg, as quoted by Siviwe Feketha in Ramaphosa slams Zuma's tenure, calls on ANC to tackle divisions https://www.msn.com/en-za/news/politics/ramaphosa-slams-zumas-tenure-calls-on-anc-to-tackle-divisions/ar-BBNMdMN, IOL (30 September 2018)

"Inside Track", PC Magazine (22 October 1996)
1980s & 1990s

Speech http://hansard.millbanksystems.com/commons/1953/nov/05/foreign-affairs in the House of Commons (5 November 1953) on the British evacuation of the Suez Canal.
1950s

Source: Sexual Personae: Art and Decadence from Nefertiti to Emily Dickinson (1990), p. 429

"Myths of our Afghanistan debate" http://nypost.com/2009/10/15/myths-of-our-afghanistan-debate/, New York Post (October 15, 2009).
New York Post

2000s, 2002, State of the Union address (January 2002)
On Hinduism, On relation of Hinduism with Jainism and Buddhism

Speech http://www.nytimes.com/1987/06/10/us/biden-joins-campaign-for-the-presidency.html announcing entry into 1988 presidential race, Wilmington, Delaware (June 10, 1987)
1980s

comment on gloriaestefan.com on release of 2-CD "The Essential Gloria Estefan" (October 4, 2006)
2007, 2008

2010s, 2017, Speech at "Spirit of Liberty: At Home, In the World" event (2017)

Source: Letter To My Undiscovered Self (2012) http://www.davidmyatt.info/letter-to-self.html

2000s, 2002, State of the Union address (January 2002)

Remarks at Bowie State University ceremony (17 May 2013) http://www.whitehouse.gov/the-press-office/2013/05/17/remarks-first-lady-bowie-state-university-commencement-ceremony
2010s
from his letter to Alfred H. Barr, Jr. 6 November, 1955; as cited in the text of 'The Baziotes Memorial Exhibition' and its accompanying catalogue by Lawrence Alloway; Solomon R. Guggenheim Museum 1965, p. 11
1950s

Speech to Chelsea Conservative Association (26 July 1975) http://www.margaretthatcher.org/document/102750
Leader of the Opposition

Speech delivered at Patna University Convocation on 27th November 1937.