diff --git a/lifelib/libraries/savings/CashValue_ME_EX4/Projection/__init__.py b/lifelib/libraries/savings/CashValue_ME_EX4/Projection/__init__.py
index 129aab6..599a5f3 100644
--- a/lifelib/libraries/savings/CashValue_ME_EX4/Projection/__init__.py
+++ b/lifelib/libraries/savings/CashValue_ME_EX4/Projection/__init__.py
@@ -1205,7 +1205,7 @@ def mort_rate(t):
     # return mort_table_reindexed().reindex(
     #     mi, fill_value=0).set_axis(model_point().index, inplace=False)
 
-    return pd.Series(0, index=model_point().index).values
+    return np.zeros(len(model_point().index))
 
 
 def mort_rate_mth(t):
@@ -1431,7 +1431,7 @@ def pols_new_biz(t):
         * :func:`model_point`
 
     """
-    return model_point()['policy_count'].where(duration_mth(t) == 0, other=0).values
+    return model_point()['policy_count'].values * (duration_mth(t) == 0)
 
 
 def prem_to_av(t):
@@ -1491,11 +1491,8 @@ def premium_pp(t):
     #     model_point().index, inplace=False)
     # return np.around(sum_assured() * prem_rates, 2)
 
-    sp = model_point()['premium_pp'].where((premium_type() == 'SINGLE') & (duration_mth(t) == 0), other=0).values
-    lp = model_point()['premium_pp'].where(
-        (premium_type() == 'LEVEL') & (duration_mth(t) < 12 * policy_term()),
-        other=0).values
-    return sp + lp
+    return model_point()['premium_pp'].values * ((premium_type() == 'SINGLE') & (duration_mth(t) == 0) |
+                                                 (premium_type() == 'LEVEL') & (duration_mth(t) < 12 * policy_term()))
 
 
 def premium_type():
@@ -1900,9 +1897,12 @@ def surr_charge_rate(t):
         * :func:`surr_charge_max_idx`
         * :func:`surr_charge_table_stacked`
     """
-    ind_row = surr_charge_table.index.searchsorted(np.minimum(duration(t), surr_charge_max_idx()), side='right') - 1
-    ind_col = surr_charge_table.columns.searchsorted(surr_charge_id(), side='right') - 1  # TODO: not clear how it should work with has_surr_charge()
-    return surr_charge_table.values.flat[ind_col + ind_row * len(surr_charge_table.columns)]
+    ind_row = np.minimum(duration(t), surr_charge_max_idx())
+    return surr_charge_table.values.flat[surr_charge_table_column() + ind_row * len(surr_charge_table.columns)]
+
+
+def surr_charge_table_column():
+    return surr_charge_table.columns.searchsorted(surr_charge_id(), side='right') - 1
 
 
 def surr_charge_table_stacked():
diff --git a/lifelib/libraries/savings/savings_example4.ipynb b/lifelib/libraries/savings/savings_example4.ipynb
index ed1ad85..f966ddd 100644
--- a/lifelib/libraries/savings/savings_example4.ipynb
+++ b/lifelib/libraries/savings/savings_example4.ipynb
@@ -41,7 +41,7 @@
     {
      "data": {
       "text/plain": [
-       "1.2689610000234097"
+       "1.2499775000000004"
       ]
      },
      "execution_count": 3,
@@ -82,7 +82,7 @@
     {
      "data": {
       "text/plain": [
-       "0.526920499978587"
+       "0.2862044000000008"
       ]
      },
      "execution_count": 6,
@@ -149,7 +149,7 @@
     {
      "data": {
       "text/plain": [
-       "7.84547259984538"
+       "8.0889741"
       ]
      },
      "execution_count": 9,
@@ -190,7 +190,7 @@
     {
      "data": {
       "text/plain": [
-       "3.8828028000425547"
+       "2.3929682999999997"
       ]
      },
      "execution_count": 12,
@@ -295,70 +295,70 @@
        "  <tbody>\n",
        "    <tr>\n",
        "      <th>surr_charge_rate(t)</th>\n",
-       "      <td>0.626154</td>\n",
-       "      <td>36.491786</td>\n",
+       "      <td>0.697034</td>\n",
+       "      <td>39.238824</td>\n",
        "    </tr>\n",
        "    <tr>\n",
        "      <th>inv_return_mth(t)</th>\n",
-       "      <td>0.291798</td>\n",
-       "      <td>17.005771</td>\n",
+       "      <td>0.338032</td>\n",
+       "      <td>19.029207</td>\n",
        "    </tr>\n",
        "    <tr>\n",
        "      <th>premium_pp(t)</th>\n",
-       "      <td>0.206414</td>\n",
-       "      <td>12.029663</td>\n",
+       "      <td>0.146663</td>\n",
+       "      <td>8.256274</td>\n",
        "    </tr>\n",
        "    <tr>\n",
-       "      <th>claim_pp(t, kind)</th>\n",
-       "      <td>0.077510</td>\n",
-       "      <td>4.517216</td>\n",
+       "      <th>pols_new_biz(t)</th>\n",
+       "      <td>0.069975</td>\n",
+       "      <td>3.939195</td>\n",
        "    </tr>\n",
        "    <tr>\n",
-       "      <th>claims(t, kind)</th>\n",
-       "      <td>0.063502</td>\n",
-       "      <td>3.700866</td>\n",
+       "      <th>inv_income_pp(t)</th>\n",
+       "      <td>0.069556</td>\n",
+       "      <td>3.915600</td>\n",
        "    </tr>\n",
        "    <tr>\n",
-       "      <th>pols_if_at(t, timing)</th>\n",
-       "      <td>0.038705</td>\n",
-       "      <td>2.255718</td>\n",
+       "      <th>claims(t, kind)</th>\n",
+       "      <td>0.064405</td>\n",
+       "      <td>3.625641</td>\n",
        "    </tr>\n",
        "    <tr>\n",
-       "      <th>av_pp_at(t, timing)</th>\n",
-       "      <td>0.034805</td>\n",
-       "      <td>2.028384</td>\n",
+       "      <th>expenses(t)</th>\n",
+       "      <td>0.035827</td>\n",
+       "      <td>2.016841</td>\n",
        "    </tr>\n",
        "    <tr>\n",
-       "      <th>inv_return_table()</th>\n",
-       "      <td>0.031250</td>\n",
-       "      <td>1.821226</td>\n",
+       "      <th>pols_maturity(t)</th>\n",
+       "      <td>0.032865</td>\n",
+       "      <td>1.850092</td>\n",
        "    </tr>\n",
        "    <tr>\n",
-       "      <th>expenses(t)</th>\n",
-       "      <td>0.029133</td>\n",
-       "      <td>1.697868</td>\n",
+       "      <th>claim_pp(t, kind)</th>\n",
+       "      <td>0.032804</td>\n",
+       "      <td>1.846696</td>\n",
        "    </tr>\n",
        "    <tr>\n",
-       "      <th>inv_income(t)</th>\n",
-       "      <td>0.027631</td>\n",
-       "      <td>1.610330</td>\n",
+       "      <th>prem_to_av_pp(t)</th>\n",
+       "      <td>0.031291</td>\n",
+       "      <td>1.761523</td>\n",
        "    </tr>\n",
        "  </tbody>\n",
        "</table>\n",
        "</div>"
       ],
       "text/plain": [
-       "                       duration   dur_perc\n",
-       "surr_charge_rate(t)    0.626154  36.491786\n",
-       "inv_return_mth(t)      0.291798  17.005771\n",
-       "premium_pp(t)          0.206414  12.029663\n",
-       "claim_pp(t, kind)      0.077510   4.517216\n",
-       "claims(t, kind)        0.063502   3.700866\n",
-       "pols_if_at(t, timing)  0.038705   2.255718\n",
-       "av_pp_at(t, timing)    0.034805   2.028384\n",
-       "inv_return_table()     0.031250   1.821226\n",
-       "expenses(t)            0.029133   1.697868\n",
-       "inv_income(t)          0.027631   1.610330"
+       "                     duration   dur_perc\n",
+       "surr_charge_rate(t)  0.697034  39.238824\n",
+       "inv_return_mth(t)    0.338032  19.029207\n",
+       "premium_pp(t)        0.146663   8.256274\n",
+       "pols_new_biz(t)      0.069975   3.939195\n",
+       "inv_income_pp(t)     0.069556   3.915600\n",
+       "claims(t, kind)      0.064405   3.625641\n",
+       "expenses(t)          0.035827   2.016841\n",
+       "pols_maturity(t)     0.032865   1.850092\n",
+       "claim_pp(t, kind)    0.032804   1.846696\n",
+       "prem_to_av_pp(t)     0.031291   1.761523"
       ]
      },
      "execution_count": 15,
@@ -415,54 +415,54 @@
        "  </thead>\n",
        "  <tbody>\n",
        "    <tr>\n",
-       "      <th>surr_charge_rate(t)</th>\n",
-       "      <td>0.204015</td>\n",
-       "      <td>37.341396</td>\n",
+       "      <th>premium_pp(t)</th>\n",
+       "      <td>0.033878</td>\n",
+       "      <td>10.744304</td>\n",
        "    </tr>\n",
        "    <tr>\n",
-       "      <th>premium_pp(t)</th>\n",
-       "      <td>0.115471</td>\n",
-       "      <td>21.134984</td>\n",
+       "      <th>mort_rate_mth(t)</th>\n",
+       "      <td>0.032263</td>\n",
+       "      <td>10.231875</td>\n",
        "    </tr>\n",
        "    <tr>\n",
-       "      <th>pv_claims(kind)</th>\n",
-       "      <td>0.031336</td>\n",
-       "      <td>5.735535</td>\n",
+       "      <th>surr_charge_rate(t)</th>\n",
+       "      <td>0.024496</td>\n",
+       "      <td>7.768857</td>\n",
        "    </tr>\n",
        "    <tr>\n",
-       "      <th>inv_return_table()</th>\n",
-       "      <td>0.023608</td>\n",
-       "      <td>4.320994</td>\n",
+       "      <th>duration(t)</th>\n",
+       "      <td>0.019624</td>\n",
+       "      <td>6.223781</td>\n",
        "    </tr>\n",
        "    <tr>\n",
-       "      <th>lapse_rate(t)</th>\n",
-       "      <td>0.022686</td>\n",
-       "      <td>4.152201</td>\n",
+       "      <th>inv_return_table()</th>\n",
+       "      <td>0.018503</td>\n",
+       "      <td>5.868249</td>\n",
        "    </tr>\n",
        "    <tr>\n",
-       "      <th>prem_to_av_pp(t)</th>\n",
-       "      <td>0.018686</td>\n",
-       "      <td>3.420122</td>\n",
+       "      <th>pv_claims(kind)</th>\n",
+       "      <td>0.018216</td>\n",
+       "      <td>5.776984</td>\n",
        "    </tr>\n",
        "    <tr>\n",
-       "      <th>av_change(t)</th>\n",
-       "      <td>0.016086</td>\n",
-       "      <td>2.944244</td>\n",
+       "      <th>claims(t, kind)</th>\n",
+       "      <td>0.018125</td>\n",
+       "      <td>5.748327</td>\n",
        "    </tr>\n",
        "    <tr>\n",
-       "      <th>commissions(t)</th>\n",
-       "      <td>0.015623</td>\n",
-       "      <td>2.859585</td>\n",
+       "      <th>av_at(t, timing)</th>\n",
+       "      <td>0.016349</td>\n",
+       "      <td>5.185010</td>\n",
        "    </tr>\n",
        "    <tr>\n",
-       "      <th>premiums(t)</th>\n",
-       "      <td>0.015507</td>\n",
-       "      <td>2.838290</td>\n",
+       "      <th>prem_to_av_pp(t)</th>\n",
+       "      <td>0.015626</td>\n",
+       "      <td>4.955751</td>\n",
        "    </tr>\n",
        "    <tr>\n",
-       "      <th>std_norm_rand()</th>\n",
-       "      <td>0.012620</td>\n",
-       "      <td>2.309915</td>\n",
+       "      <th>pols_new_biz(t)</th>\n",
+       "      <td>0.015588</td>\n",
+       "      <td>4.943653</td>\n",
        "    </tr>\n",
        "  </tbody>\n",
        "</table>\n",
@@ -470,16 +470,16 @@
       ],
       "text/plain": [
        "                     duration   dur_perc\n",
-       "surr_charge_rate(t)  0.204015  37.341396\n",
-       "premium_pp(t)        0.115471  21.134984\n",
-       "pv_claims(kind)      0.031336   5.735535\n",
-       "inv_return_table()   0.023608   4.320994\n",
-       "lapse_rate(t)        0.022686   4.152201\n",
-       "prem_to_av_pp(t)     0.018686   3.420122\n",
-       "av_change(t)         0.016086   2.944244\n",
-       "commissions(t)       0.015623   2.859585\n",
-       "premiums(t)          0.015507   2.838290\n",
-       "std_norm_rand()      0.012620   2.309915"
+       "premium_pp(t)        0.033878  10.744304\n",
+       "mort_rate_mth(t)     0.032263  10.231875\n",
+       "surr_charge_rate(t)  0.024496   7.768857\n",
+       "duration(t)          0.019624   6.223781\n",
+       "inv_return_table()   0.018503   5.868249\n",
+       "pv_claims(kind)      0.018216   5.776984\n",
+       "claims(t, kind)      0.018125   5.748327\n",
+       "av_at(t, timing)     0.016349   5.185010\n",
+       "prem_to_av_pp(t)     0.015626   4.955751\n",
+       "pols_new_biz(t)      0.015588   4.943653"
       ]
      },
      "execution_count": 16,
@@ -529,28 +529,33 @@
        "  <tbody>\n",
        "    <tr>\n",
        "      <th>surr_charge_rate(t)</th>\n",
-       "      <td>0.626154</td>\n",
-       "      <td>0.204015</td>\n",
+       "      <td>0.697034</td>\n",
+       "      <td>0.024496</td>\n",
        "    </tr>\n",
        "    <tr>\n",
        "      <th>inv_return_mth(t)</th>\n",
-       "      <td>0.291798</td>\n",
-       "      <td>0.002037</td>\n",
+       "      <td>0.338032</td>\n",
+       "      <td>0.000000</td>\n",
        "    </tr>\n",
        "    <tr>\n",
        "      <th>premium_pp(t)</th>\n",
-       "      <td>0.206414</td>\n",
-       "      <td>0.115471</td>\n",
+       "      <td>0.146663</td>\n",
+       "      <td>0.033878</td>\n",
        "    </tr>\n",
        "    <tr>\n",
-       "      <th>claim_pp(t, kind)</th>\n",
-       "      <td>0.077510</td>\n",
-       "      <td>0.002008</td>\n",
+       "      <th>pols_new_biz(t)</th>\n",
+       "      <td>0.069975</td>\n",
+       "      <td>0.015588</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>inv_income_pp(t)</th>\n",
+       "      <td>0.069556</td>\n",
+       "      <td>0.015507</td>\n",
        "    </tr>\n",
        "    <tr>\n",
        "      <th>claims(t, kind)</th>\n",
-       "      <td>0.063502</td>\n",
-       "      <td>0.000000</td>\n",
+       "      <td>0.064405</td>\n",
+       "      <td>0.018125</td>\n",
        "    </tr>\n",
        "  </tbody>\n",
        "</table>\n",
@@ -558,11 +563,12 @@
       ],
       "text/plain": [
        "                          df1       df4\n",
-       "surr_charge_rate(t)  0.626154  0.204015\n",
-       "inv_return_mth(t)    0.291798  0.002037\n",
-       "premium_pp(t)        0.206414  0.115471\n",
-       "claim_pp(t, kind)    0.077510  0.002008\n",
-       "claims(t, kind)      0.063502  0.000000"
+       "surr_charge_rate(t)  0.697034  0.024496\n",
+       "inv_return_mth(t)    0.338032  0.000000\n",
+       "premium_pp(t)        0.146663  0.033878\n",
+       "pols_new_biz(t)      0.069975  0.015588\n",
+       "inv_income_pp(t)     0.069556  0.015507\n",
+       "claims(t, kind)      0.064405  0.018125"
       ]
      },
      "execution_count": 17,
@@ -593,7 +599,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.10.6"
+   "version": "3.9.7"
   }
  },
  "nbformat": 4,