i have a dataset as below

    4.8856
    4.8914
    4.9125
    4.9338
    4.9563
    4.993
    4.9947
    4.9947
    4.995
    5.2932
    4.981
    4.981
    4.981
    4.982
    4.982
    4.982
    4.982
    4.983
    4.983
    4.984
    4.984

Histogram

[![Histogram][1]][1]


  [1]: https://i.sstatic.net/Ou1a5.jpg


When i use 3*IQR in boxplot R to detect outliers, it gives me 10 records out of 21 as outliers. However, as i can see from histogram there is mainly 1 outlier (the right most) which i need to filter out. 

what would be the recommended outlier detection method for this data?