## 1. Why do some figures not add-up?

### a) Census Rounding:

To maximize privacy, Statistics Canada rounds data to multiples
of five or ten. However, figures on population counts are not rounded since they do not provide
information on the characteristics of these populations.

### b) Twenty percent Sample Data:

Not all data is collected from the entire population.
Some questions, such as those related to income, are asked to only 20 percent of the population (Census
long questionnaire) and used to estimate values for the entire population.

## 2. Warning for Top 5 Tables

### a) Threshold:

The top five variables within a given table are determined by
their ranking within Peel, not necessarily a particular ward. If you wish to obtain the top five for
a ward, contact us.

### b) Comparability:

As the top five in a census year may vary to another census
year, some variables may not be comparable. The Peel Data Centre provides trend analysis where possible
under the 2001-2006 Change Tables. If you wish to retrieve a full set of figures, contact us.

## 3. Reading the Percent Change Table Correctly:

This table summarises two distinct types of changes for 2001-2006.

### a) Percent Change:

When dealing with absolute numbers, Percent Change Table
displays percent changes (B-A)/A, where A = Census Data Year 2001 and B = Census Data Year 2006. For
example, a percent change is used to compare the change in number of immigrants in 2001 and 2006.

### b) Change in Proportion:

When dealing with proportions (percentages), the Percent
Change Table displays a simple change in proportion (B-A) as opposed to a percent change (B-A)/A. For
example, a change in proportion is used to compare the change in the proportions of immigrants out of
the total population in 2001 and 2006.

## 4. What is the difference between cells containing zero (0) and those with a hyphen (-)?

### a) Zero (0):

An absence of a given characteristic. For example, a zero under
category "Seniors 65+" means there were no seniors in that ward.

### b) Hyphen (-):

Missing data that should not be interpreted as an absence of
a given characteristic.

Hyphens also appear in percent change and/or change in
proportions whenever the denominator was zero. Hyphen also applies to 2006 variables that changed
in definition since the 2001 census, or were not reported on in the 2001 census and could not have
percentage change (from 2001-2006) calculated. For example, if in 2001 there were zero immigrants
in an area, and in 2006 there were 15, the percent change will be shown by a hyphen (-), as you
can't divide by zero.

## 5. Where do I find complete figures that explain percentage change?

When analyzing figures for percentage change, please
consult the 2001 and 2006 tables for full figures. If the figures you are looking for are not present,
contact us to obtain additional information.