The Irish provisions cost annually about £300, and the English supplies
about £1000, not including such extra outlays as that of £1355 in 1793 for
new stills, worms, and coppers. Local expenditures were probably reckoned
in currency. Converted into sterling, the salary list amounted to about
£500, and the local outlay for medical services, wharfage, and petty
supplies came to a like amount. Taxes, manager's commissions, and the
depreciation of apparatus must have amounted collectively to £800. The
net death-loss of slaves, not including that from the breaking-in of new
negroes, averaged about two and a quarter per cent.; that of the mules and
oxen ten per cent. When reckoned upon the numbers on hand in 1796 when the
plantation with 470 slaves was operating with very little outside help,
these losses, which must be replaced by new purchases if the scale of
output was to be maintained, amounted to about £900. Thus a total of £4000
sterling is reached as the average current expense in years when no mishaps
occurred.

The crops during the years of the record averaged 311 hogsheads of sugar,
sixteen hundredweight each, and 133 puncheons of rum, 110 gallons each.
This was about the common average on the island, of two-thirds as many
hogsheads as there were slaves of all ages on a plantation.[23] If the
prices had been those current in the middle of the eighteenth century these
crops would have yielded the proprietor great profits. But at £15 per
hogshead and £10 per puncheon, the prices generally current in the island
in the seventeen-nineties, the gross return was but about £6000 sterling,
and the net earnings of the establishment accordingly not above £2000. The
investment in slaves, mules and oxen was about £28,000, and that in land,
buildings and equipment according to the island authorities, would reach a
like sum.[24] The net earnings in good years were thus less than four per
cent. on the investment; but the liability to hurricanes, earthquakes,