Stocks and flows

House construction during a year measures building activity completed over a period, so it is a flow. The total number or value of houses available at the end of the year is a stock because it is measured at a particular date. Construction may add to the housing stock, but the two measures have different time dimensions. Therefore, C is correct.

The expression per day specifies a quantity produced or extracted over a time interval, so it is a flow. A stock would be the total quantity available at a particular point, such as the mineral remaining in a mine on a date. Stocks can be physical or monetary, so the other claims are incorrect.

The reliable rule is to inspect the time reference. A stock is measured at a particular point, such as capital on 31 March, whereas a flow is measured over a period, such as national income during a year. The size or name of a variable does not decide its classification. Option C is correct.

The opening cash balance is measured at the beginning of the year, a specific point in time, so it is a stock. Cash receipts during the year accumulate over an interval and therefore form a flow. The balance is a position, while receipts are transactions occurring through time. Consequently, the correct order is stock and flow, given in option A.

A stock is a quantity measured at a particular point of time, whereas a flow is measured over a period. The total balance of bank deposits on a specific date shows how much money exists at that moment, so it is a stock. Amounts deposited during a year, month, or week record activity over time and are therefore flows.

A flow measures an economic activity over a period of time. The amount deposited into a bank account during one month records deposits made throughout that month, so it is a flow. By contrast, a balance measured today, on a particular day, or at the end of the year is measured at a point in time and is a stock.

The fundamental basis for distinguishing a stock from a flow is the time reference. A stock measures a quantity existing at a particular point, such as wealth on 31 March. A flow measures an amount generated, received, or spent during a period, such as annual income. Price, ownership, and whether something is a good or service do not determine the classification.

Capital formation means the creation or addition of productive assets during a specified period. Since it records an increase in the capital stock over time, it is measured as a flow. The resulting capital stock, in contrast, is measured at a point of time.

Depreciation measures the reduction in the value of a fixed asset over an accounting period, so it is a flow. Money supply and bank balance generally refer to quantities existing at a point in time and are stocks. Monthly rent is received during a month and is also a flow, so option B is incorrect.

A change flow measures the increase or decrease in a stock over a specified period. The increase in capital stock during the year is measured between two points in time and therefore is a change flow. Wealth, bank balance, and population stated on a date are stock quantities because they describe levels existing at particular points.

Cash received during the year records receipts occurring throughout a stated period, so it is a flow. The word “during” indicates that the amount accumulates over time. Cash balance on a date, money supply today, and inventory at year end are balances measured at particular points and are therefore stocks.

The governing concept is the measurement date, not simply the presence of a calendar word. A stock records an amount existing at one particular point in time. “Cash balance at year end” is measured on the final date of the year, so it is a stock even though the phrase refers to a yearly accounting period. Option C is therefore correct. Sales throughout the year, monthly salary, and weekly expenditure are each totals accumulated over intervals, so they are flows. The phrase “year end” identifies a specific closing date, whereas “throughout,” “monthly,” and “weekly” describe activity over time. This distinction prevents the common mistake of classifying every annual or monthly expression as a flow without examining what is actually measured.

The governing concept is the accounting distinction between flows and stocks. Annual sales in an income statement represent transactions and revenue generated over the entire year, so they are measured over a period and are a flow. A liability in a balance sheet represents the amount owed by the firm at the balance-sheet date, so it is measured at a particular point in time and is a stock. Option B correctly gives this order: annual sales are a flow and liability is a stock. Option A reverses the categories, option C incorrectly treats the dated liability as a period amount, and option D confuses classification by time with the separate accounting concept of income. The statement in which an item appears does not alone determine its type; its measurement period does.

The governing concept is the distinction between a stock and a flow. A flow is measured over a specified period, such as a day, month, or year, whereas a stock is measured at one particular point in time. A per-year rate describes an amount generated, earned, spent, or changed during each year, so its time reference is an interval. Therefore, it is generally classified as a flow, making option B correct. A stock would be expressed as a balance on a date, such as wealth on 31 March or inventory at the end of the year. Option A and option D describe point-in-time measurements, while option C is not the standard economic classification. The units may be rupees, but the time reference determines the category.

The governing rule is that a stock is measured at a particular point in time, while a flow is measured over a period. A total amount recorded on a specific date represents a balance existing at that moment. Examples include cash held on 31 March, the value of wealth on a birthday, inventory at closing time, or outstanding debt on the last day of a month. Thus option B, stock, is correct. Annual expenditure and monthly income in options C and D are flows because they accumulate during an interval rather than being observed at only one instant. Option A is also incorrect because a flow requires a period such as a month or year. The word total does not itself decide the answer; the decisive clue is the specific date.

A house, considered as an asset owned by a household, has a value measured at a particular point in time and is therefore a stock. Rent payment is made or recorded over a period, such as a month, and is therefore a flow. Thus option A correctly pairs them.

A factory building is a fixed asset existing at a point in time, so its value is a stock. Annual output is the quantity produced during a year, so it is a flow. Similarly, sales and interest payments are period-based flows, whereas a cash balance or total liability on a date is a stock.

This question applies both parts of the stock-flow rule. Income earned during one year is measured across the interval from the beginning to the end of that year; it is therefore a flow. Wealth stated on a particular date is a balance existing at one point in time, so it is a stock. Option B correctly pairs the two classifications. Option A reverses them. Options C and D confuse the unit or the fact of measurement with the relevant time dimension. Both income and wealth may be expressed in rupees, but currency does not make a variable a stock or a flow. The period of observation determines income's classification, while the date of observation determines wealth's classification. Hence B is unambiguous.

Consumption during a month refers to spending or using goods and services throughout a time interval. Because it is measured over that monthly period, it is a flow. Consumer debt at the end of the month is the outstanding liability recorded on a particular date, so it is a stock. Therefore option B is correct. Option A reverses the classifications. Option C is wrong because debt at the end of the month is not the amount borrowed throughout the month; it is the balance remaining at a point in time. Option D is also incorrect because neither consumption nor debt is automatically income. The decisive test is the time reference: “during a month” signals a flow, whereas “at the end” signals a stock.

A bank balance at the end of the month is the amount held on a specified date or endpoint, so it is a stock. Monthly income, weekly expenditure and yearly investment are recorded as activities occurring over periods, so they are flows. The word “end” signals a balance only when it refers to an amount held then.

An income statement reports revenue, expenses, and profit earned over an accounting period, so its items are generally flows. A balance sheet reports assets, liabilities, and equity on a particular date, so its items are generally stocks. This is a useful accounting application of time reference.

Saving is classified according to its time reference. Saving made during the current year means the part of income not consumed over that entire year; it is measured across a period and is therefore a flow. Option C is correct because the question asks when saving is not a stock. Accumulated saving over many years is a balance built up and held at a point in time, so it is a stock. A year-end saving balance is also a stock because it records the amount existing on a date. Savings deposited today and shown as a balance likewise represent a stock, even though the deposit transaction itself occurred during a day. The distinction is between saving as a period activity and savings as an accumulated balance.

Expenditure on new capital goods during the year is investment measured over a period, so it is a flow. Total capital assets at year end, machines on a date, and total assets today are stocks because they describe capital held at particular points in time. Investment flow can add to capital stock.

The opening cash balance is an amount available at the beginning of a particular day, so it is measured at a point in time and is a stock. Cash withdrawals during the day are transactions occurring over a period, so they are a flow. The withdrawals may reduce the later balance, but they remain a flow.

A stock is measured at a point in time, so the phrase “on a date” is the most suitable wording. Phrases such as per month, during one year, and throughout the week refer to intervals and normally describe flows. Time language is therefore an important classification clue.