Get performance usage for c#

PerformanceManager.cs

using System.Diagnostics;

public static class PerformanceManager
{
    static PerformanceCounter cpuCounter;
    static PerformanceCounter ramCounter;

    static PerformanceManager()
    {
        cpuCounter = new PerformanceCounter();

        cpuCounter.CategoryName = "Processor";
        cpuCounter.CounterName = "% Processor Time";
        cpuCounter.InstanceName = "_Total";

        ramCounter = new PerformanceCounter("Memory", "Available MBytes");
    }

    public static string getCurrentCpuUsage()
    {
        return cpuCounter.NextValue() + "%";
    }

    public static string getAvailableRAM()
    {
        return ramCounter.NextValue() + "MB";
    }
}