radzen-blazor/RadzenBlazorDemos/Pages/WaterfallChartConfig.razor

<RadzenStack class="rz-p-0 rz-p-md-6 rz-p-lg-12">
    <RadzenCard Variant="Variant.Outlined">
        <RadzenStack Orientation="Orientation.Horizontal" AlignItems="AlignItems.Center" Gap="0.5rem">
            <RadzenLabel Text="Fill" Component="fillMode" />
            <RadzenSelectBar @bind-Value="@fillMode" TValue="FillMode" Size="ButtonSize.Small" Name="fillMode">
                <Items>
                    <RadzenSelectBarItem Value="FillMode.Gradient" Text="Gradient" />
                    <RadzenSelectBarItem Value="FillMode.Solid" Text="Solid" />
                    <RadzenSelectBarItem Value="FillMode.None" Text="None" />
                </Items>
            </RadzenSelectBar>
        </RadzenStack>
    </RadzenCard>

    <RadzenRow>
        <RadzenColumn Size="12">
            <RadzenChart Animate="true">
                <RadzenWaterfallSeries Data="@cashFlow" CategoryProperty="Label" ValueProperty="Amount"
                    SummaryProperty="IsTotal" Title="Cash Flow" FillMode="@fillMode"
                    PositiveFill="#26A69A" NegativeFill="#EF5350" SummaryFill="#42A5F5" />
                <RadzenColumnOptions Radius="3" />
                <RadzenCategoryAxis />
                <RadzenValueAxis>
                    <RadzenGridLines Visible="true" />
                    <RadzenAxisTitle Text="Amount ($)" />
                </RadzenValueAxis>
            </RadzenChart>
        </RadzenColumn>
    </RadzenRow>
</RadzenStack>

@code {
    FillMode fillMode = FillMode.Gradient;

    class DataItem
    {
        public string Label { get; set; }
        public double Amount { get; set; }
        public bool IsTotal { get; set; }
    }

    DataItem[] cashFlow = new DataItem[]
    {
        new DataItem { Label = "Revenue", Amount = 420 },
        new DataItem { Label = "Services", Amount = 210 },
        new DataItem { Label = "COGS", Amount = -170 },
        new DataItem { Label = "Gross Profit", Amount = 0, IsTotal = true },
        new DataItem { Label = "Salaries", Amount = -200 },
        new DataItem { Label = "Marketing", Amount = -80 },
        new DataItem { Label = "R&D", Amount = -50 },
        new DataItem { Label = "Net Income", Amount = 0, IsTotal = true },
    };
}