| Period | Research by | Remarks | Period | Research by | Remarks |
| 1864-1914 | Kirkaldy (for British Shipping) | 1911: best for 10 years; returns equal to those obtained by investing in 1st class securities; at times, however, shipping run at a loss | 1930-1935 (crisis) | “Tramp shipping administrative Committee” | 214 shipping companies had a ROC of only 1.45% p.a. |
| 1950-1957 | “Economist shipping share index” | 10.3% p.a. increase for shipping; 17.2% had all companies | 1958-1969 | “Economist Shipping Share index” | +3.2% up |
| 1958-1969 | “Rochdale Committee” | 3.5% p.a. (very low) for shipping | 1988-1997 | Six bulk shipping companies; 6 liner (*) companies | 7% return 8% return |
| 1990-2000 | Oslo shipping shares | A small increase in prices | 2001 | Six public tanker owners | 6.3% on equity |
| 1975-2004 | | Bulk shipping 7.2% ROI | 1975-2004 | | 4.9% ROI in tankers |