How to show data week wise for current month in ASP.NET MVC?

<pre lang="ASP.NET">
<pre>Week1 = QAScore 94%(Average)
Week2 = 95%
Week3 = 90%
Week4 = 91%

public ActionResult ChartQA()
{
            /*This Month Begin*/

            DateTime now = DateTime.Now;
            var startDate = new DateTime(now.Year, now.Month, 1);
            var endDate = startDate.AddMonths(1).AddDays(-1);
            /*This Month Ends*/

            /*Last Week Begin*/
            var mostRecentMonday = DateTime.Now.AddDays(-7).StartOfWeek(DayOfWeek.Monday);
            var weekEnd = mostRecentMonday.AddDays(7).AddSeconds(-1); //will return the end of the day on Sunday

            ViewBag.Monday = mostRecentMonday;
            ViewBag.lastWeekSunday = weekEnd;
            /*Last Week Ends*/

            /*This Week Begin*/
            var thisWeekMonday = DateTime.Now.StartOfWeek(DayOfWeek.Monday);//get week start of most recent Monday morning
            var Thisweekend = thisWeekMonday.AddDays(7).AddSeconds(-1); //will return the end of the day on Sunday
            /*This Week Ends*/

            var QMSCount = db.Chats.Where(x => System.Data.Entity.DbFunctions.TruncateTime(x.MSTChatCreatedDateTime) >= mostRecentMonday && System.Data.Entity.DbFunctions.TruncateTime(x.MSTChatCreatedDateTime)
                    <= weekEnd && x.Feedback != null && x.ChatNotFound == null).Count();

            var QMSTotal = db.Chats.Where(x => System.Data.Entity.DbFunctions.TruncateTime(x.MSTChatCreatedDateTime) >= mostRecentMonday && System.Data.Entity.DbFunctions.TruncateTime(x.MSTChatCreatedDateTime)
            <= weekEnd && x.Feedback != null && x.ChatNotFound == null).Sum(x => (float?)x.QualityScore);

            ViewBag.TodaysAudit = QMSCount;
            ViewBag.QMS = QMSTotal / QMSCount;

            var chart = new Chart();
            //chart.Width = Unit.Pixel(800);
            var area = new ChartArea();
            chart.ChartAreas.Add(area);
            var series = new Series();            
            series.Points.AddXY("Week1",  Math.Round(ViewBag.QMS));
            series.IsValueShownAsLabel = true;
            series.LabelFormat = "{0}%";
            chart.ChartAreas[0].AxisY.LabelStyle.Format = "###0\\%";
            //series.Label = "#PERCENT{P0}";
            chart.ChartAreas[0].AxisX.MajorGrid.LineWidth = 0;
            chart.ChartAreas[0].AxisX.LabelStyle.Angle = 0;
            chart.ChartAreas[0].AxisY.MajorGrid.Enabled = false;
            chart.ChartAreas[0].AxisX.LabelStyle.Interval = 1;

            series.Font = new Font("Arial", 9.0f, FontStyle.Bold);
            series.ChartType = SeriesChartType.Column;
            //series["PieLabelStyle"] = "Outside";
            chart.Series.Add(series);
            var returnStream = new MemoryStream();
            chart.ImageType = ChartImageType.Png;
            chart.SaveImage(returnStream);
            returnStream.Position = 0;
            return new FileStreamResult(returnStream, "image/png");
}

<pre lang="ASP.NET">
public static class DateTimeExtensions
    {

        public static DateTime StartOfWeek(this DateTime dt, DayOfWeek startOfWeek)
        {
            int diff = (7 + (dt.DayOfWeek - startOfWeek)) % 7;
            return dt.AddDays(-1 * diff).Date;
        }

        static GregorianCalendar _gc = new GregorianCalendar();
        public static int GetWeekOfMonth(this DateTime time)
        {
            DateTime first = new DateTime(time.Year, time.Month, 1);
            return time.GetWeekOfYear() - first.GetWeekOfYear() + 1;
        }

        static int GetWeekOfYear(this DateTime time)
        {
            return _gc.GetWeekOfYear(time, CalendarWeekRule.FirstDay, DayOfWeek.Monday);
        }
    }

<pre lang="ASP.NET">
<pre>        var result = chats.Select(c => new
        {
            ChatId = c.ChatId,
            Title = c.Title,
            Year = c.MSTChatCreatedDateTime.Year,
            Month = c.MSTChatCreatedDateTime.Month,
            WeekofMonth = c.MSTChatCreatedDateTime.GetWeekOfMonth()
        });
        //use GrouBy method to filter data per weeks.
        var reult2 = result.GroupBy(c => new { c.Year, c.Month, c.WeekofMonth }).Select(c => c);
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