Railroad earnings. In compiling railroad reports the total earnings or receipts from traffic are set
down as gross earnings and the remainder, after deducting operating expenses (cost of handling
traffic), is net earnings. To net earnings is added other income (usually derived from investments,
which are often in the form of securities held to control other roads) and the total is gross income
(as distinguished from gross earnings). From gross income are paid rentals and other charges,
interest requirements (commonly called fixed charges), etc. The remainder is designated as net
income. From it are paid dividends and what is left is surplus.  In reporting gross earnings it is the
practice to divide each month into four weeks. The first seven days are counted as the first week,
the second seven days as the second week and the third seven days as the third week, while the
remaining days of the month are counted as the fourth week. In a month of 30 days the fourth
week consists of nine days and in a month of 31 days it consists of ten days. Thus, the fourth
week may contain two Sundays.