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We present period change rates (dP/dt) for 42 RR Lyrae variables in theglobular cluster IC$\,$4499. Despite clear evidence of these period increasesor decreases, the observed period change rates are an order of magnitude largerthan predicted from theoretical models of this cluster. We find there is apreference for increasing periods, a phenomenon observed in most RR Lyrae starsin Milky Way globular clusters. The period-change rates as a function ofposition in the period-amplitude plane are used to examine possibleevolutionary effects in OoI clusters, OoII clusters, field RR Lyrae stars andthe mixed-population cluster $\omega$~ Centauri. It is found that there is nocorrelation between the period change rate and the typical definition ofOosterhoff groups. If the RR Lyrae period changes correspond with evolutionaryeffects, this would be in contrast to the hypothesis that RR Lyrae variables inOoII systems are evolved HB stars that spent their ZAHB phase on the blue sideof the instability strip. This may suggest that age may not be the primaryexplanation for the Oosterhoff types.

Period Change Similarities among the RR Lyrae Variables in Oosterhoff I and Oosterhoff II Globular Systems