I am trying to create an indicator using c# which decides the momentum rating based on the last 30 days of minutes data, every bar is 1 min. I want to rate the momentum on a scale of -10 to +10 depending on how fast it is in either direction negative is down and positive is up. I am using ninjatrader for this. right now I am just smoothing the momentum value, but I need better calculation for this. Please help.

protected override void OnBarUpdate()
    {
        if (CurrentBar < MomentumPeriod + SmoothnessPeriod + windowSize) return;

        momentumValues.Add(momentumValues.Count > 0 ? momentumValues[0] : 0);

        double smoothedMomentum = momentumValues.Count >= SmoothnessPeriod
            ? momentumValues.Skip(momentumValues.Count - SmoothnessPeriod).Take(SmoothnessPeriod).Average()
            : momentumValues.Last();

        smoothedMomentumValues.Add(smoothedMomentum);
        lastSmoothedMomentumValues.Add(smoothedMomentum);

        if (lastSmoothedMomentumValues.Count > windowSize)
        {
            lastSmoothedMomentumValues.RemoveAt(0);
        }

        double minMomentum = smoothedMomentumValues.Min();
        double maxMomentum = smoothedMomentumValues.Max();
        double momentumRange = maxMomentum - minMomentum;
        double momentumRating = momentumRange != 0
            ? ((smoothedMomentum - minMomentum) / momentumRange * 20.0) - 10.0
            : 0;

        momentumRatings.Append(momentumRating);

        RoundedSmoothedValue = Math.Round(smoothedMomentum, 2);
        double momentumScore = CalculateMomentumScore(RoundedSmoothedValue);
        ImmediateMomentum = momentumScore <= -7 ? "Down" : momentumScore >= 7 ? "Up" : "NA";

        SolidColorBrush brushColor = momentumScore <= -7 ? Brushes.LightPink : momentumScore >= 7 ? Brushes.LightGreen : Brushes.White;

        UpdateOverallMomentum(RoundedSmoothedValue);

        if (RoundedSmoothedValue >= 7.0 || RoundedSmoothedValue <= -7.0)
        {
            PrintMomentumInfo(Time[0], ImmediateMomentum, OverallMomentum, minMomentum, maxMomentum, momentumRating, smoothedMomentum, RoundedSmoothedValue, (int)momentumScore, brushColor);
        }

        DrawMomentumInfo(OverallMomentum, ImmediateMomentum, momentumScore, RoundedSmoothedValue, (TextPosition)DisplayPosition, brushColor, DisplayFont);
    }


    private void UpdateOverallMomentum(double roundedSmoothedValue)
    {
        if (roundedSmoothedValue >= 7.0 && (OverallMomentum == "" || OverallMomentum == "Down"))
        {
            OverallMomentum = "Up";
        }
        else if (roundedSmoothedValue <= -7.0 && (OverallMomentum == "" || OverallMomentum == "Up"))
        {
            OverallMomentum = "Down";
        }
    }

    public int CalculateMomentumScore(double smoothedValue)
    {
        int momentumScore = (int)Math.Round(smoothedValue);
        return Clamp(momentumScore, -10, 10);
    }

    private int Clamp(int value, int min, int max)
    {
        if (value < min) return min;
        if (value > max) return max;
        return value;
    }