diff --git a/tests/Makefile.am b/tests/Makefile.am
index 60ac51c550e8d9a3120a01517cec76612441da81..257af1500e99dae2eeb9a2a41e4b2e4137609bd7 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -85,6 +85,8 @@ MODFILES = \
fs2000/fs2000_missing_data.mod \
fs2000/fs2000_sd.mod \
fs2000/fs2000_mode_compute_8.mod \
+ fs2000/fs2000_dseries_a.mod \
+ fs2000/fs2000_dseries_b.mod \
homotopy/homotopy1_test.mod \
homotopy/homotopy2_test.mod \
homotopy/homotopy3_test.mod \
diff --git a/tests/fs2000/fsdat_simul_dseries.m b/tests/fs2000/fsdat_simul_dseries.m
new file mode 100644
index 0000000000000000000000000000000000000000..2dd9c2e2d68b7943253ac9e03523213fdc62459e
--- /dev/null
+++ b/tests/fs2000/fsdat_simul_dseries.m
@@ -0,0 +1,828 @@
+% File created on 15-Jul-2014 15:44:30.
+
+FREQ__ = 4;
+INIT__ = '1950Q1';
+
+NAMES__ = {'P_obs'; 'Y_obs'; 'gp_obs'; 'gy_obs'};
+TEX__ = {'P\_obs'; 'Y\_obs'; 'gp\_obs'; 'gy\_obs'};
+
+P_obs = [
+ 1
+ 0.99948573
+ 1.0068249
+ 1.0141211
+ 1.0073149
+ 0.99884398
+ 1.0237035
+ 1.0349636
+ 1.036819
+ 1.0247366
+ 1.0242391
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+ 1.0065684
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+ 0.97281734
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+ 0.9355791
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+ 1.453154
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+ 1.4266407];
+
+Y_obs = [
+ 1
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+ 1.0371688
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+ 0.94070026
+ 0.93172987];
+
+gp_obs = [
+ 1.0079715
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+ 1.0152677
+ 1.0011653
+ 0.99950061
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+
+gy_obs = [
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+