Stewart, Basil, "Restoration of Palestine", (In reference to the Empayar Achaemenid), p. 3 (2003).
While estimates for the Empayar Achaemenid range from 10–80+ juta, most prefer 50 juta. Prevas (2009, p. 14) estimates 10 juta 1. Langer (2001, p. 40) estimates around 16 juta 2. McEvedy and Jones (2001, p. 50) estimates 17 juta 3. Strauss (2004, p. 37) estimates about 20 juta 4. Ward (2009, p. 16) estimates at 20 juta 5. Aperghis (2007, p. 311) estimates 32 juta 6. Scheidel (2009, p. 99) estimates 35 juta 7. Zeinert (1996, p. 32) estimates 40 juta 8. Rawlinson and Schauffler (1898, p. 270) estimates possibly 50 juta 9. Astor (1899, p. 56) estimates almost 50 juta 10. Lissner (1961, p. 111) estimates probably 50 juta 11. Milns (1968, p. 51) estimates some 50 juta 12. Hershlag (1980, p. 140) estimates nearly 50 juta 13. Yarshater (1996, p. 47) estimates by 50 juta 14. Daniel (2001, p. 41) estimates at 50 juta 15. Meyer and Andreades (2004, p. 58) estimates to 50 juta 16. Pollack (2004, p. 7) estimates about 50 juta 17. Jones (2004, p. 8) estimates over 50 juta 18. Safire (2007, p. 627) estimates in 50 juta 19. Dougherty (2009, p. 6) estimates about 70 juta 20. Richard (2008, p. 34) estimates nearly 70 juta 21. Mitchell (2004, p. 16) estimates over 70 juta 22. Hanson (2001, p. 32) estimates almost 75 juta 23. West (1913, p. 85) estimates about 75 juta 24. Zenos (1889, p. 2) estimates exactly 75 juta 25. Cowley (1999 and 2001, p. 17) estimates possibly 80 juta 26. Cook (1904, p. 277) estimates exactly 80 juta 27.
census.gov
While estimates for the Empayar Achaemenid range from 10–80+ juta, most prefer 50 juta. Prevas (2009, p. 14) estimates 10 juta 1. Langer (2001, p. 40) estimates around 16 juta 2. McEvedy and Jones (2001, p. 50) estimates 17 juta 3. Strauss (2004, p. 37) estimates about 20 juta 4. Ward (2009, p. 16) estimates at 20 juta 5. Aperghis (2007, p. 311) estimates 32 juta 6. Scheidel (2009, p. 99) estimates 35 juta 7. Zeinert (1996, p. 32) estimates 40 juta 8. Rawlinson and Schauffler (1898, p. 270) estimates possibly 50 juta 9. Astor (1899, p. 56) estimates almost 50 juta 10. Lissner (1961, p. 111) estimates probably 50 juta 11. Milns (1968, p. 51) estimates some 50 juta 12. Hershlag (1980, p. 140) estimates nearly 50 juta 13. Yarshater (1996, p. 47) estimates by 50 juta 14. Daniel (2001, p. 41) estimates at 50 juta 15. Meyer and Andreades (2004, p. 58) estimates to 50 juta 16. Pollack (2004, p. 7) estimates about 50 juta 17. Jones (2004, p. 8) estimates over 50 juta 18. Safire (2007, p. 627) estimates in 50 juta 19. Dougherty (2009, p. 6) estimates about 70 juta 20. Richard (2008, p. 34) estimates nearly 70 juta 21. Mitchell (2004, p. 16) estimates over 70 juta 22. Hanson (2001, p. 32) estimates almost 75 juta 23. West (1913, p. 85) estimates about 75 juta 24. Zenos (1889, p. 2) estimates exactly 75 juta 25. Cowley (1999 and 2001, p. 17) estimates possibly 80 juta 26. Cook (1904, p. 277) estimates exactly 80 juta 27.
There are several different estimates for the Empayar Rom. Scheidel (2006, p. 2) estimates 60 juta. Goldsmith (1984, p. 263) estimates 55 juta. Beloch (1886, p. 507) estimates 54 juta. Maddison (2006, p. 51, 120) estimates 48 juta. Roman Empire Population estimates 65 juta (while mentioning several other estimates between 55 juta and 120 juta).