Absolute values can be:

• values that show the frequency of appearence of a specific event, e.g. the number of accidents in a year
• values in a known scale, e.g. temperature in ° Celsius

Relative values can be:

• values that show their relation with something else, e.g. population density
• partial values shown in relation to total values, usually in percentages, e.g. rate of public traffic on total traffic
• values calculated on average, e.g. the average value of births in a country
• values that show the increase or decrease of a phenomenon, e.g. decrease of minimum wages in 2013

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