\$ 1,240.66
  A              14                 519            \$ 78.90
  M              12                 847            \$ 203.45
  K              10                 474            \$ 292.02
  Q              3                  150            \$ 24.60
  Y              1                  1,026          \$ 61.56

  : Budget Summary by Activities[]{data-label="ActBudg"}

If we take out the category data processing, research participation, captcha solving, testing, installing and “other”, the remaining activities are purely for promotional purposes. This leaves 1,665,138 tasks, or 89.7% of the whole. It should be added that many of the install tasks appear to be promotional (see section \[Smartphone\]). Counting these in would make the figure even higher. However, since for many such campaigns this aspect is impossible to tell, they are left out.

A similar summary for the platforms is given in table \[PlatBudg\]. The first column is the platform name, the rest is the same as before. The table is ordered by the descending number of campaigns.

  **Platform**     **\# campaigns**   **\# tasks**   **\# total budget**
  ---------------- ------------------ -------------- ---------------------
  Smartphone       1102               231,892        \$ 27,702.07
  Google+          823                57,203         \$ 18,960.50
  Other            797                349,937        \$ 31,333.06
  Twitter          747                83,731         \$ 14,047.21
  Facebook         666                115,967        \$ 15,657.86
  YouTube          616                248,914        \$ 29,322.28
  Reddit           539                77,104         \$ 5,434.15
  Redacted         501                132,401        \$ 13,397.94
  Google           330                261,923        \$ 18,672.37
  RDT              