| Frequency | Number of dividends |
| Annually | 0 |
| Semi-annually | 0 |
| Quarterly | 145 |
| Monthly | 0 |
| Irregularly | 0 |
| 'none' | 0 |
Dividend payment timing:
| Month | Number of dividends |
| January | 0 |
| February | 0 |
| March | 37 |
| April | 0 |
| May | 0 |
| June | 36 |
| July | 0 |
| August | 0 |
| September | 36 |
| October | 0 |
| November | 0 |
| December | 36 |
| Status | Number |
| Cancelled | 0 |
| Discontinued | 0 |
| Omitted | 0 |
| Year | Dividends paid | Increase from previous year | CAGR to 2012 from | Bumpiness to 2012 from |
| 1977 | $ 0.08750 | 8.677% | 4 | |
| 1978 | $ 0.10500 | 20.001% | 8.361% | 4 |
| 1979 | $ 0.12333 | 17.460% | 8.096% | 4 |
| 1980 | $ 0.13667 | 10.811% | 8.012% | 4 |
| 1981 | $ 0.15167 | 10.977% | 7.918% | 4 |
| 1982 | $ 0.16875 | 11.263% | 7.808% | 4 |
| 1983 | $ 0.17917 | 6.172% | 7.865% | 4 |
| 1984 | $ 0.19792 | 10.466% | 7.774% | 4 |
| 1985 | $ 0.22000 | 11.158% | 7.650% | 4 |
| 1986 | $ 0.23250 | 5.681% | 7.727% | 4 |
| 1987 | $ 0.24500 | 5.376% | 7.822% | 4 |
| 1988 | $ 0.25750 | 5.102% | 7.937% | 4 |
| 1989 | $ 0.28875 | 12.136% | 7.758% | 4 |
| 1990 | $ 0.31875 | 10.390% | 7.639% | 4 |
| 1991 | $ 0.33375 | 4.706% | 7.781% | 4 |
| 1992 | $ 0.34875 | 4.494% | 7.948% | 4 |
| 1993 | $ 0.36750 | 5.376% | 8.085% | 4 |
| 1994 | $ 0.40000 | 8.844% | 8.043% | 5 |
| 1995 | $ 0.46000 | 15.000% | 7.648% | 4 |
| 1996 | $ 0.50250 | 9.239% | 7.549% | 4 |
| 1997 | $ 0.55250 | 9.950% | 7.391% | 5 |
| 1998 | $ 0.60500 | 9.502% | 7.241% | 5 |
| 1999 | $ 0.66625 | 10.124% | 7.023% | 5 |
| 2000 | $ 0.72750 | 9.193% | 6.844% | 5 |
| 2001 | $ 0.76750 | 5.498% | 6.967% | 5 |
| 2002 | $ 0.77750 | 1.303% | 7.551% | 5 |
| 2003 | $ 0.78875 | 1.447% | 8.251% | 5 |
| 2004 | $ 0.80750 | 2.377% | 9.009% | 5 |
| 2005 | $ 0.84500 | 4.644% | 9.647% | 5 |
| 2006 | $ 0.93000 | 10.059% | 9.578% | 5 |
| 2007 | $ 1.08750 | 16.935% | 8.163% | 4 |
| 2008 | $ 1.23000 | 13.103% | 6.962% | 4 |
| 2009 | $ 1.32500 | 7.724% | 6.710% | 4 |
| 2010 | $ 1.35000 | 1.887% | 9.206% | 3 |
| 2011 | $ 1.43500 | 6.296% | 12.195% | 0 |
| 2012 | $ 1.61000 | 12.195% |
| Yield | Price |
| 0.5% | $322.00 |
| 1.0% | $161.00 |
| 1.5% | $107.33 |
| 2.0% | $ 80.50 |
| 2.5% | $ 64.40 |
| 3.0% | $ 53.67 |
| 3.5% | $ 46.00 |
| 4.0% | $ 40.25 |
| 4.5% | $ 35.78 |
| 5.0% | $ 32.20 |
| 5.5% | $ 29.27 |
| 6.0% | $ 26.83 |
| 6.5% | $ 24.77 |
| 7.0% | $ 23.00 |
| 7.5% | $ 21.47 |
| 8.0% | $ 20.12 |
| 8.5% | $ 18.94 |
| 9.0% | $ 17.89 |
| 9.5% | $ 16.95 |
| 10.0% | $ 16.10 |