Edexcel GCSE Statistics Time series and index numbers overview quiz quiz

$20$

$22$

$24$

$88$

To make the recorded values in the data set numerically larger

To remove the need to draw a graph of the time series at all

To smooth out seasonal variation and reveal the trend

To convert every figure in the data into a percentage

$20\%$

$80\%$

$125\%$

$25\%$

The price has risen by $15\%$

The price has fallen by $15\%$

The price has risen by $115\%$

The price is unchanged

$\frac{\text{base value}}{\text{current value}} \times 100$

$\frac{\text{current value}}{\text{base value}} \times 100$

current value $-$ base value

$\frac{\text{current value}}{\text{base value}}$

$6$ per $1000$

$60$ per $1000$

$12$ per $1000$

$120$ per $1000$

The four-point moving average value for that period

The full range of the whole time series data set

The base value taken from the very first year

The mean seasonal effect for that season

The cost of living (price inflation)

The total size of the whole national economy

The unemployment rate across the country

The annual birth rate of the population

The total number of separate items contained in the whole basket

The different importance (weight) of each item

Only the base year and nothing else

The seasonal effect of each quarter

At the first of the four values it averages

At the last of the four values it averages

At the centre of the values it averages

At the very start of the following year

Simply to make the numbers smaller for no particular reason at all

Because the crude rate formula always has to come out equal to $1000$

To convert the crude rate directly into an index number

So populations of different sizes can be compared fairly

It adjusts for differing age structures so populations compare fairly

It is much quicker and easier to calculate than a crude rate is

It does not require any population figure at all in order to be worked out

It always produces a larger value than the crude rate does