XmlSerializer serializer = new XmlSerializer(typeof(Daily_response));
using (TextReader reader = new StringReader(xml))
{
    Daily_response result = (Daily_response)serializer.Deserialize(reader);
    foreach (var day in result.Data.Day)
    {
        br.Registrations += Convert.ToInt32(day.Conversions);
        br.Visits += Convert.ToInt32(day.Clicks);
        br.NetRevenue += Convert.ToDecimal(day.Revenue.Replace(".", ","));
    }
}