24. Some reports suggest that increase in climate variability or extremes has taken place in recent decades. However, there are inadequate data to determine whether such global changes have occurred consistently over the 20th century. On regional scales there is clear evidence of changes in some extremes and climate variability indicators - for example, fewer frosts in several widespread areas; and an increase in the proportion of rainfall from extreme events over the contiguous states of the USA. It can also be seen that the economic damages from weather related disasters have increased dramatically, although much of this may be attributed to a greater number of people living in vulnerable areas..