How often are JMX Cassandra metrics reset?

[Donald Smith]

I'm using JMX to retrieve Cassandra metrics.   I notice that  Max and Count are 
cumulative and aren't reset.    How often are the stats for Mean, 
99tthPercentile, etc reset back to zero?

For example, 99thPercentile shows as 1.5 mls. Over how many minutes?

ClientRequest/Read/Latency:
    LatencyUnit = MICROSECONDS
    FiveMinuteRate = 1.12
    FifteenMinuteRate = 1.11
    RateUnit = SECONDS
    MeanRate = 1.65
    OneMinuteRate = 1.13
    EventType = calls
   Max = 237,373.37
    Count = 961,312
    50thPercentile = 383.2
    Mean = 908.46
    Min = 95.64
    StdDev = 3,034.62
    75thPercentile = 626.34
    95thPercentile = 954.31
    98thPercentile = 1,443.11
    99thPercentile = 1,472.4
    999thPercentile = 1,858.1

Donald A. Smith | Senior Software Engineer
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C: (206) 819-5965
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dona...@audiencescience.com<mailto:dona...@audiencescience.com>

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