| Left: Examples of fits to $\Dzero$ (top), $\Dplus$ (middle) and $\Dstar$ (bottom) impact-parameter distributions in the $\pt$ intervals $3<\pt<4~\gevc$, $5<\pt<6~\gevc$ and $6<\pt<8~\gevc$, respectively. The curves show the fit functions describing the prompt, feed-down and background contributions, as well as their sum, as described in the text. Right: fraction of prompt $\Dzero$ (top), $\Dplus$ (middle) and $\Dstar$ (bottom) raw yield as a function of $\pt$ compared to the FONLL-based approach. The results from the data-driven method are shown as square markers with the error bars (boxes) representing the statistical (systematic) uncertainty. The arrow in the interval $1<\pt<2~\gev/c$ represents the minimum value within a 95\% confidence level. The central values of $f_{\rm prompt}$ from the FONLL-based approach are shown by the dashed line and their uncertainty by the red boxes. |