Identifying points on a trendline

[datadummy]

I currently have a trend line with the following trend line equation, y=-0.0131x+580.53. I am trying to determine the start and end points of the trend line. I have 19 data points please let me know if sharing the data points would be helpful or are they relevant considering I am addressing the trend line?

 

[John_w]

Try this macro. It calculates and displays the (x,y) start and end points of the trendline for the first chart on the active sheet.

Public Sub Trendline_Start_End_Points()

    Dim ch As Chart
    Dim ser As Series
    Dim xVals As Variant
    Dim trLine As Trendline
    Dim p1 As Long, p2 As Long
    Dim m As Double, b As Double
    
    Set ch = ActiveSheet.ChartObjects(1).Chart
    Set ser = ch.SeriesCollection(1)
    xVals = ser.XValues
    
    'Extract m and b values from linear trendline equation, y = mx + b
    
    For Each trLine In ser.Trendlines
        If trLine.DisplayEquation Then
            With trLine.DataLabel
                p2 = InStr(.Text, "x")
                b = Trim(Mid(.Text, p2 + 1))
                p1 = InStrRev(.Text, "=", p2)
                m = Trim(Mid(.Text, p1 + 1, p2 - p1 - 1))
            End With
        End If
    Next
    
    MsgBox "Trendline start point: x=" & xVals(1) & " y=" & m * xVals(1) + b & vbCrLf & _
           "Trendline end point: x=" & xVals(UBound(xVals)) & " y=" & m * xVals(UBound(xVals)) + b

End Sub