Table:
Unnamed: 0 | Year | Name | City | Country | Guests of Honor | Size
1st | 1939 | Nycon I | New York, New York | United States | Frank R. Paul | 200
2nd | 1940 | Chicon I | Chicago, Illinois | United States | E. E. "Doc" Smith | 128
3rd | 1941 | Denvention I | Denver, Colorado | United States | Robert A. Heinlein | 90
4th | 1946 | Pacificon I | Los Angeles, California | United States | A. E. van Vogt / E. Mayne Hull | 130
5th | 1947 | Philcon I | Philadelphia, Pennsylvania | United States | John W. Campbell, Jr. | 200
6th | 1948 | Torcon I | Toronto, Ontario | Canada | Robert Bloch (Pro) / Bob Tucker (fan) | 200
7th | 1949 | Cinvention | Cincinnati, Ohio | United States | Lloyd A. Eshbach (pro) / Ted Carnell (fan) | 190
8th | 1950 | Norwescon | Portland, Oregon | United States | Anthony Boucher | 400
9th | 1951 | Nolacon I | New Orleans, Louisiana | United States | Fritz Leiber | 190
10th | 1952 | TASFiC (Chicon II) | Chicago, Illinois | United States | Hugo Gernsback | 870
11th | 1953 | Philcon II | Philadelphia, Pennsylvania | United States | Willy Ley | 750
12th | 1954 | SFCon | San Francisco, California | United States | John W. Campbell, Jr. | 700
13th | 1955 | Clevention | Cleveland, Ohio | United States | Isaac Asimov (pro) / Sam Moskowitz (mystery GoH) | 380
14th | 1956 | NyCon II | New York, New York | United States | Arthur C. Clarke | 850
15th | 1957 | Loncon I | London | UK | John W. Campbell, Jr. | 268
16th | 1958 | Solacon | South Gate, California | United States | Richard Matheson | 211
17th | 1959 | Detention | Detroit, Michigan | United States | Poul Anderson (pro) / John Berry (fan) | 371
18th | 1960 | Pittcon | Pittsburgh, Pennsylvania | United States | James Blish | 568
19th | 1961 | Seacon | Seattle, Washington | United States | Robert A. Heinlein | 300
20th | 1962 | Chicon III | Chicago, Illinois | United States | Theodore Sturgeon | 730
21st | 1963 | Discon I | Washington, D.C. | United States | Murray Leinster | 600
22nd | 1964 | Pacificon II | Oakland, California | United States | Leigh Brackett (pro) / Edmond Hamilton (pro) / Forrest J Ackerman (fan) | 523
23rd | 1965 | Loncon II | London | UK | Brian W. Aldiss | 350
24th | 1966 | Tricon | Cleveland, Ohio | United States | L. Sprague de Camp | 850
25th | 1967 | Nycon 3 | New York, New York | United States | Lester del Rey (pro) / Bob Tucker (fan) | 1,500
26th | 1968 | Baycon | Berkeley, California | United States | Philip José Farmer (pro) / Walter J. Daugherty (fan) | 1,430
27th | 1969 | St. Louiscon | St. Louis, Missouri | United States | Jack Gaughan (pro) / Eddie Jones (fan) | 1,534
28th | 1970 | Heicon '70 | Heidelberg | West Germany | E.C. Tubb (UK) / Robert Silverberg (US) / Herbert W. Franke (Germany) / Elliot K. Shorter (fan) | 620
29th | 1971 | Noreascon I | Boston, Massachusetts | United States | Clifford D. Simak (pro) / Harry Warner, Jr. (fan) | 1,600
30th | 1972 | L.A.con I | Los Angeles, California | United States | Frederik Pohl (pro) / Buck & Juanita Coulson (fan) | 2,007
31st | 1973 | Torcon II | Toronto | Canada | Robert Bloch (Pro) / William Rotsler (fan) | 2,900
32nd | 1974 | Discon II | Washington, D.C. | United States | Roger Zelazny (pro) / Jay Kay Klein (fan) | 3,587
33rd | 1975 | Aussiecon 1 | Melbourne, Victoria | Australia | Ursula K. Le Guin (pro) / Susan Wood (fan) / Mike Glicksohn (fan) / Donald Tuck (Australian) | 606
34th | 1976 | MidAmeriCon | Kansas City, Missouri | United States | Robert A. Heinlein | 3,014
35th | 1977 | SunCon | Miami Beach, Florida | United States | Jack Williamson (pro) / Robert A. Madle (fan) | 3,240 / (4,200)
36th | 1978 | IguanaCon II | Phoenix, Arizona | United States | Harlan Ellison (pro) / Bill Bowers (fan) | 4,700
37th | 1979 | Seacon '79 | Brighton | UK | Brian Aldiss (UK) / Fritz Leiber (US) / Harry Bell (fan) | 3,114
38th | 1980 | Noreascon Two | Boston, Massachusetts | United States | Damon Knight (pro) / Kate Wilhelm (pro) / Bruce Pelz (fan) | 5,850
39th | 1981 | Denvention Two | Denver, Colorado | United States | Clifford D. Simak (pro) / C.L. Moore (pro) / Rusty Hevelin (fan) | 3,792
40th | 1982 | Chicon IV | Chicago, Illinois | United States | A. Bertram Chandler (pro) / Frank Kelly Freas (pro) / Lee Hoffman (fan) | 4,275
41st | 1983 | ConStellation | Baltimore, Maryland | United States | John Brunner (pro) / David A. Kyle (fan) | 6,400
42nd | 1984 | L.A.con II | Anaheim, California | United States | Gordon R. Dickson (pro) / Dick Eney (fan) | 8,365
43rd | 1985 | Aussiecon Two | Melbourne, Victoria | Australia | Gene Wolfe (pro) / Ted White (fan) | 1,599
44th | 1986 | ConFederation | Atlanta, Georgia | United States | Ray Bradbury (pro) / Terry Carr (fan) | 5,811
45th | 1987 | Conspiracy '87 | Brighton | UK | Doris Lessing (UK) / Alfred Bester (US) / Boris and Arkady Strugatsky (USSR) / Jim Burns (artist) / Ray Harryhausen (film) / Joyce and Ken Slater (fan) / David Langford (special fan) | 4,009 / (5,425)
46th | 1988 | Nolacon II | New Orleans, Louisiana | United States | Donald A. Wollheim (pro) / Roger Sims (fan) | 5,300
47th | 1989 | Noreascon 3 | Boston, Massachusetts | United States | Andre Norton (pro) / Betty and Ian Ballantine (pro) / The Stranger Club (fan) | 6,837 / (7,795)
48th | 1990 | ConFiction | The Hague | Netherlands | Harry Harrison (pro) / Wolfgang Jeschke (pro) / Joe Haldeman (pro) / Andrew I. Porter (fan) | 3,580
49th | 1991 | Chicon V | Chicago, Illinois | United States | Hal Clement (pro) / Martin H. Greenberg (pro) / Richard Powers (pro) / Jon and Joni Stopa (fan) | 5,661
50th | 1992 | MagiCon | Orlando, Florida | United States | Jack Vance (pro) / Vincent Di Fate (artist) / Walter A. Willis (fan) | 5,319 / (6,368)
51st | 1993 | ConFrancisco | San Francisco, California | United States | Larry Niven / Alicia Austin / Tom Digby (fan) / Jan Howard Finder / Mark Twain (Dead GoH) | 6,602
52nd | 1994 | ConAdian | Winnipeg | Canada | Anne McCaffrey (pro) / George Barr (artist) / Robert Runte (fan) | 3,570 / (7,725)
53rd | 1995 | Intersection | Glasgow, Scotland | UK | Samuel R. Delany (writer) / Gerry Anderson (media) / Les Edwards (artist) / Vin¢ Clarke (fan) | 4,173 / (6,524)
54th | 1996 | L.A.con III | Anaheim, California | United States | James White (writer) / Roger Corman (media) / Elsie Wollheim (special) / Takumi and Sachiko Shibano (fan) | 6,703
55th | 1997 | LoneStarCon 2 | San Antonio, Texas | United States | Algis Budrys (pro) / Michael Moorcock (pro) / Don Maitz (artist) / Roy Tackett (fan) | 4,634 / (5,614)
56th | 1998 | BucConeer | Baltimore, Maryland | United States | C. J. Cherryh / Milton A. Rothman / Stanley Schmidt / Michael Whelan / J. Michael Straczynski (special) | 6,572
57th | 1999 | Aussiecon Three | Melbourne, Victoria | Australia | Gregory Benford, author / George Turner, author / Bruce Gillespie, fan | 1,626 / (2,872)
58th | 2000 | Chicon 2000 | Chicago, Illinois | United States | Ben Bova (author) / Bob Eggleton (artist) / Jim Baen (editor) / Bob & Anne Passovoy (fan) | 5,794 / (6,574)
59th | 2001 | Millennium Philcon | Philadelphia, Pennsylvania | United States | Greg Bear (author) / Stephen Youll (artist) / Gardner Dozois (editor) / George H. Scithers (fan) | 4,840 / (6,269)
60th | 2002 | ConJosé | San Jose, California | United States | Vernor Vinge (author) / David Cherry (artist) / Bjo & John Trimble (fan) / Ferdinand Feghoot (imaginary) | 5,162 / (5,916)
61st | 2003 | Torcon 3 | Toronto | Canada | George R. R. Martin (author) / Frank Kelly Freas (artist) / Mike Glyer (fan) / Robert Bloch (GoHst of Honor) | 3,834 / (4,986)
62nd | 2004 | Noreascon 4 | Boston, Massachusetts | United States | Terry Pratchett (pro) / William Tenn (pro) / Jack Speer (fan) / Peter Weston (fan) | 5,651 / (7,485)
63rd | 2005 | Interaction | Glasgow, Scotland | UK | Greg Pickersgill / Christopher Priest / Robert Sheckley / Lars-Olov Strandberg / Jane Yolen | 4,115 / (5,202)
64th | 2006 | L.A.con IV | Anaheim, California | United States | Connie Willis (Author) / James Gurney (Artist) / Howard DeVore (fan) / Frankie Thomas (Special) | 5,738 / (6,291)
65th | 2007 | Nippon 2007 | Yokohama | Japan | Sakyo Komatsu (author) / David Brin (author) / Takumi Shibano (fan) / Yoshitaka Amano (artist) / Michael Whelan (artist) | 3,348 / (5,149)
66th | 2008 | Denvention 3 | Denver, Colorado | United States | Lois McMaster Bujold (pro) / Tom Whitmore (fan) / Rick Sternbach (artist) | 3,752
67th | 2009 | Anticipation | Montréal, Québec | Canada | Neil Gaiman (pro) / Elisabeth Vonarburg (pro) / Taral Wayne (fan) / David Hartwell (editor) / Tom Doherty (publisher) | 3,925 / (4,499)
68th | 2010 | Aussiecon Four | Melbourne, Victoria | Australia | Kim Stanley Robinson (author) / Robin Johnson (fan) / Shaun Tan (artist) | 2,101 / (3,462)
69th | 2011 | Renovation | Reno, Nevada | United States | Tim Powers / Ellen Asher / Boris Vallejo / Charles N. Brown (in memoriam) | 4,112 / (5,526)
70th | 2012 | Chicon 7 | Chicago, Illinois | United States | Mike Resnick (author) / Rowena Morrill (artist) / Story Musgrave (astronaut) / Peggy Rae Sapienza (fan) / Jane Frank (agent) / Sy Liebergot (special guest) / John Scalzi (toastmaster) | 4,743 / (6,197)
71st | 2013 | LoneStarCon 3 | San Antonio, Texas | United States | Ellen Datlow / James Gunn / Willie Siros / Norman Spinrad / Darrell K. Sweet (in memoriam) / Paul Cornell (toastmaster) / Leslie Fish / Joe R. Lansdale | 4,311 / (6,060)
72nd | 2014 | Loncon 3 | London | UK | Iain M. Banks (in memoriam) / John Clute / Chris Foss / Malcolm Edwards / Jeanne Gomoll / Robin Hobb / Bryan Talbot | 
73rd | 2015 | Sasquan | Spokane, Washington | United States | Brad Foster / David Gerrold / Vonda McIntyre / Tom Smith / Leslie Turek |

Question: are the years listed in consecutive order or not?
Answer: yes

Question: how many countries are listed?
Answer: 7

Question: city in which doris lessing made her "guest of honor" appearance
Answer: Brighton

Question: city in which worldcon was held the year after it was held in yokohama
Answer: Denver, Colorado

Question: what year saw the greatest size?
Answer: 1984

Question: before 1970 how many conventions had more than 1,000 attendees?
Answer: 3

Question: number of worldcons held outside the united states
Answer: 19

Question: how many times was chicago listed as a city?
Answer: 7

Question: the last convention held outside of europe or north america was held when?
Answer: 2010

Question: what is the last year on the chart?
Answer: 2015

Question: how many conventions in total have been held in chicago?
Answer: 7