These are the rankings for year end 2012, dated December 10, 2012.
Here is a list of the average ranking of the top 10 players each birth year with the number of top 100 players in parentheses. An asterisk indicated that year does includes less than 10 ranked players.
1970*: 98 (1)
1974*: 189
1975*: 507
1976*: 462
1977*: 610
1978*: 911
1979*: 473
1980*: 410 (2)
1981*: 349 (2)
1982: 74 (7)
1983: 114 (4)
1984: 90 (6)
1985: 73 (8)
1986: 62 (9)
1987: 30 (11)
1988: 66 (8)
1989: 58 (7)
1990: 36 (14)
1991: 68 (11)
1992: 105 (4)
1993: 109 (4)
1994: 143 (2)
1995: 282
1996: 446
1997: 752
1998*: 913
Now without further ado, the rankings:
Compiled: Dec 10, 2012 (year end)
1970
98-Kimiko
Date-Krumm (JPN)
1974
189-Jill
Craybas (USA)
1975
507-Anne
Kremer (LUX)
1976
462-Romana
Tedjakusuma (INA)
1977
153-Tamarine
Tanasugarn (THA)
1066-Rushmi
Chakravarthi (IND)
1978
911-Vladimira
Uhlirova (CZE)
1979
117-Greta
Arn (HUN)
235-Catalina
Castano (COL)
246-Severine
Beltrame (FRA)
390-Katalin
Marosi (HUN)
698-Diana
Ospina (USA)
1151-Sandra
Martinovic (BIH)
1980
24-Venus
Williams (USA)
35-Francesca
Schiavone (ITA)
134-Alberta
Brianti (ITA)
227-Mervana
Jugic-Salkic (BIH)
238-Petra
Rampre (SLO)
476-Alexandra
Stevenson (USA)
1030-Remi
Tezuka (JPN)
1112-Zuzana
Ondraskova (CZE)
1981
3-Serena
Williams (USA)
48-Lourdes
Dominiguez Lino (ESP)
102-Stephanie
Foretz-Gacon (FRA)
257-Kristina
Barrois (GER)
322-Rika
Fujiwara (JPN)
648-Abigail
Spears (USA)
1063-Natalie
Grandin (RSA)
1982
7-Na
Li (CHN)
12-Nadia
Petrova (RUS)
28-Klara
Zakopalova (CZE)
45-Flavia
Pennetta (ITA)
50-Anabel
Medina Garrigues (ESP)
94-Melinda
Czink (HUN)
100-Eleni
Daniilidou (GRE)
105-Mirjana
Lucic-Baroni (CRO)
138-Anastasia
Rodionova (AUS)
163-Maria
J. Martinez Sanchez (ESP)
1983
16-Roberta
Vinci (ITA)
26-Jie
Zheng (CHN)
32-Daniela
Hantuchova (SVK)
81-Iveta
Benesova (CZE)
132-Yvonne
Meusberger (AUT)
143-Anne
Keothavong (GBR)
161-Virginie
Razzano (FRA)
173-Elena
Baltacha (GBR)
179-Yuliya
Beygelzimer (UKR)
195-Monique
Adamczak (AUS)
1984
9-Samantha
Stosur (AUS)
11-Marion
Bartoli (FRA)
41-Sofia
Arvidsson (SWE)
60-Chanelle
Scheepers (RSA)
82-Galina
Voskoboeva (KAZ)
95-Vera
Zvonareva (RUS)
108-Edina
Gallovits-Hall (ROU)
125-Eva
Birnerova (CZE)
157-Laura
Pous-Tio (ESP)
207-Akgul
Amanmuradova (UZB)
1985
19-Kaia
Kanepi (EST)
22-Jelena
Jankovic (SRB)
46-Lucie
Hradecka (CZE)
55-Petra
Cetkovska (CZE)
71-Svetlana
Kuznetsova (RUS)
77-Mandy
Minella (LUX)
79-Nina
Bratchikova (RUS)
88-Mathilde
Johansson (FRA)
101-Casey
Dellacqua (AUS)
169-Bethanie
Mattek-Sands (USA)
1986
21-Varvara
Lepchenko (USA)
25-Su-Wei
Hsieh (TPE)
40-Shuai
Peng (CHN)
54-Kirsten
Flipkens (BEL)
61-Romina
Oprandi (ITA)
64-Andrea
Hlavackova (CZE)
65-Pauline
Parmentier (FRA)
68-Elena
Vesnina (RUS)
90-Barbora
Zahlavova Strycova (CZE)
135-Claire
Feuerstein (FRA)
1987
2-Maria
Sharapova (RUS)
6-Sara
Errani (ITA)
13-Ana
Ivanovic (SRB)
14-Maria
Kirilenko (RUS)
17-Lucie
Safarova (CZE)
29-Yaroslava
Shvedova (KAZ)
42-Tsvetana
Pironkova (BUL)
43-Aleksandra
Wozniak (CAN)
58-Monica
Niculescu (ROU)
74-Shahar
Peer (ISR)
1988
5-Angelique
Kerber (GER)
18-Julia
Goerges (GER)
20-Ekaterina
Makarova (RUS)
34-Carla
Suarez Navarro (ESP)
57-Olga
Govortsova (BLR)
62-Magdalena
Rybarikova (SVK)
66-Marina
Erakovic (NZL)
73-Johanna
Larsson (SWE)
162-Teliana
Pereira (BRA)
164-Irena
Pavlovic (FRA)
1989
1-Victoria
Azarenka (BLR)
4-Agnieszka
Radwanska (POL)
15-Dominika
Cibulkova (SVK)
23-Yanina
Wickmayer (BEL)
37-Sabine
Lisicki (GER)
69-Vania
King (USA)
89-Alexandra
Panova (RUS)
111-Sesil
Karatancheva (KAZ)
114-Julia
Cohen (USA)
118-Vesna
Dolonc (SRB)
1990
8-Petra
Kvitova (CZE)
10-Caroline
Wozniacki (DEN)
27-Sorana
Cirstea (ROU)
30-Tamira
Paszek (AUT)
31-Urszula
Radwanska (POL)
39-Mona
Barthel (GER)
44-Alize
Cornet (FRA)
51-Anna
Tatishvili (GEO)
52-Irina-Camelia
Begu (ROU)
70-Jamie
Hampton (USA)
1991
36-Anastasia
Pavlyuchenkova (RUS)
47-Simona
Halep (ROU)
56-Bojana
Jovanovski (SRB)
59-Petra
Martic (CRO)
63-Kiki
Bertens (NED)
75-Camila
Giorgi (ITA)
76-Polona
Hercog (SLO)
84-Melanie
Oudin (USA)
87-Kai-Chen
Chang (TPE)
96-Misaki
Doi (JPN)
1992
33-Christina
McHale (USA)
49-Heather
Watson (GBR)
78-Lara
Arruabarrena-Vecino (ESP)
99-Maria-Teresa
Torro-Flor (ESP)
104-Kristyna
Pliskova (CZE)
121-Karolina
Pliskova (CZE)
129-Maria
Joao Koehler (POR)
141-Dinah
Pfizenmaier (GER)
142-Paula
Ormaechea (ARG)
155-Nastassja
Burnett (ITA)
1993
38-Sloane
Stephens (USA)
67-Timea
Babos (HUN)
85-Kristina
Mladenovic (FRA)
93-Lauren
Davis (USA)
110-Garbine
Muguruza (ESP)
113-Jana
Cepelova (SVK)
130-Michelle
Larcher de Brito (POR)
133-Monica
Puig (PUR)
149-Caroline
Garcia (FRA)
171-Aleksandra
Krunic (SRB)
1994
53-Laura
Robson (GBR)
80-Annika
Beck (GER)
112-Elina
Svitolina (UKR)
139-Saisai
Zheng (CHN)
147-Eugenie
Bouchard (CAN)
151-Jessica
Pegula (USA)
182-Kateryna
Kozlova (UKR)
183-Grace
Min (USA)
186-Anna
Schmiedlova (SVK)
196-Anna-Lena
Friedsam (GER)
1995
107-Yulia
Putintseva (KAZ)
137-Madison
Keys (USA)
190-Irina
Khromacheva (RUS)
226-Carina
Witthoeft (GER)
272-Samantha
Crawford (USA)
343-Anna
Danilina (KAZ)
361-Anna
Shkudun (UKR)
380-Sachia
Vickery (USA)
395-Alexandra
Kiick (USA)
406-Anett
Kontaveit (EST)
1996
109-Donna
Vekic (CRO)
176-Ashleigh
Barty (AUS)
393-Mayo
Hibi (JPN)
467-Sara
Sorribes Tormo (ESP)
498-Taylor
Townsend (USA)
533-Rutuja
Bhosale (IND)
535-Barbara
Haas (AUT)
545-Brooke
Austin (USA)
600-Marianna
Zakarlyuk (UKR)
601-Anne-Liz
Jeukeng (USA)
1997
605-Francoise
Abanda (CAN)
615-Belinda
Bencic (SUI)
621-Nadia
Podoroska (ARG)
709-Veronika
Kudermetova (RUS)
721-Jelena
Ostapenko (LAT)
758-Ivana
Jorovic (SRB)
792-Lizette
Cabrera (AUS)
877-Ana
Konjuh (CRO)
903-Radina
Dimitrova (BUL)
915-Katerina
Stewart (USA)
1998
913-Tornado
Alicia Black (USA)
