How to Show Maximum and Minimum point in List Point Plot

Question

I have a list point of data per day. I want to plot this list of points in Mathematica and so that the maximum and minimum identified by for example red point. How can I figure it out? In the following my my data are available. Thanks

ClearAll["Global`*"]
dataMT103891062day = {{{95, 5, 1}, 0.0764}, {{95, 5, 2}, 
0.0774}, {{95, 5, 3}, 0.0824}, {{95, 5, 4}, 0.0795}, {{95, 5, 5}, 
0.0887}, {{95, 5, 6}, 0.0867}, {{95, 5, 7}, 0.0794}, {{95, 5, 8}, 
0.0731}, {{95, 5, 9}, 0.0686}, {{95, 5, 10}, 
0.0797}, {{95, 5, 11}, 0.0792}, {{95, 5, 12}, 
0.0874}, {{95, 5, 13}, 0.0814}, {{95, 5, 14}, 
0.0809}, {{95, 5, 15}, 0.0775}, {{95, 5, 16}, 
0.0757}, {{95, 5, 17}, 0.0717}, {{95, 5, 18}, 
0.0811}, {{95, 5, 19}, 0.0773}, {{95, 5, 20}, 
0.0743}, {{95, 5, 21}, 0.0767}, {{95, 5, 22}, 
0.0744}, {{95, 5, 23}, 0.0787}, {{95, 5, 24}, 
0.0772}, {{95, 5, 25}, 0.0916}, {{95, 5, 26}, 
0.0801}, {{95, 5, 27}, 0.0724}, {{95, 5, 28}, 
0.0636}, {{95, 5, 29}, 0.0699}, {{95, 5, 30}, 
0.0634}, {{95, 5, 31}, 0.0695}};
DateListPlot[dataMT103891062day, PlotLegends -> "Load Coefficient"] 

Answer 1

You can use MaximalByand MinimalBy,

{max, min} = {MaximalBy[#, Last], MinimalBy[#, Last]} &@ dataMT103891062day;

Plot them using Epilogattribute.

DateListPlot[dataMT103891062day, PlotLegends -> "Load Coefficient", 
 Epilog -> {PointSize -> Medium, Red, Point@max, Point@min}]

To label the max and min points Labeled can be used as follows.

DateListPlot[{dataMT103891062day, Labeled[min, min, {Right}], 
  Labeled[max, max, {Right}]}, PlotLabel -> "Load Coefficient", 
 Epilog -> {PointSize -> Medium, Red, Point@max, Point@min}, ImageSize -> Medium]