1. importar los datos

library(ggplot2)
library(forecast)
library(readxl)
ivae_ts <- read_excel("C:/Users/user/Desktop/ivae_AI.xlsx", 
    col_types = c("skip", "skip", "numeric"))
data=ivae_ts %>% ts(start = c(2005,1),frequency = 12)->ivae
print(ivae)
##         Jan    Feb    Mar    Apr    May    Jun    Jul    Aug    Sep    Oct
## 2005  87.77  88.52  89.72  91.15  91.98  92.61  91.94  91.26  92.23  92.16
## 2006  93.48  93.55  93.17  93.58  93.91  94.29  93.37  93.10  93.08  93.04
## 2007  92.37  94.92  94.51  94.33  94.45  95.30  95.94  96.38  97.00  97.81
## 2008  97.57  97.74  97.31  96.89  96.35  96.67  97.15  96.99  97.70  98.49
## 2009  96.75  95.15  94.55  93.90  93.95  94.56  95.34  95.90  96.37  96.53
## 2010  92.84  92.27  90.42  90.29  90.82  91.64  93.48  93.71  92.02  89.92
## 2011  89.31  89.81  90.14  89.99  90.05  89.18  89.02  89.06  88.93  89.81
## 2012  91.64  92.64  93.96  95.54  96.37  95.86  94.15  93.44  93.22  94.27
## 2013  96.04  96.24  95.77  95.52  95.81  96.06  96.63  96.95  97.35  97.51
## 2014  98.50  98.74  99.04  98.99  99.18  99.74  99.94 100.51 100.95 101.45
## 2015 100.36 100.10 101.26 102.66 103.35 103.45 102.69 103.02 103.87 106.29
## 2016 107.18 107.07 106.61 107.65 108.42 108.79 109.29 109.35 109.50 109.99
## 2017 110.46 110.81 109.72 109.64 109.70 109.26 110.32 111.12 111.24 111.83
## 2018 112.76 112.79 111.28 110.94 110.98 110.62 111.16 111.97 112.60 113.86
## 2019 115.60 116.08 114.30 114.48 114.88 114.45 114.73 114.98              
##         Nov    Dec
## 2005  92.39  92.97
## 2006  93.19  92.24
## 2007  98.29  97.51
## 2008  98.51  97.79
## 2009  96.82  93.41
## 2010  88.82  88.47
## 2011  90.67  91.22
## 2012  95.30  95.81
## 2013  97.83  97.90
## 2014 101.68 101.29
## 2015 107.58 107.99
## 2016 110.25 110.72
## 2017 112.34 112.74
## 2018 114.37 114.94
## 2019

2. proyección a Seis meses

library(forecast)
modelo<-auto.arima(y = ivae)
summary(modelo)
## Series: ivae 
## ARIMA(0,1,1)(0,0,1)[12] with drift 
## 
## Coefficients:
##          ma1    sma1   drift
##       0.4228  0.3206  0.1681
## s.e.  0.0668  0.0827  0.0945
## 
## sigma^2 estimated as 0.4664:  log likelihood=-180.81
## AIC=369.62   AICc=369.85   BIC=382.28
## 
## Training set error measures:
##                        ME      RMSE       MAE          MPE      MAPE
## Training set -0.005880707 0.6751475 0.4888659 -0.008310211 0.5005399
##                   MASE       ACF1
## Training set 0.1675353 0.02398227
pronosticos<-forecast(modelo,h = 6)
autoplot(pronosticos)+xlab("Años")+ylab("indice")+theme_bw()

library(forecast)
autoplot(pronosticos$x,series = "IVAE")+autolayer(pronosticos$fitted,series = "Pronóstico")+ggtitle("Ajuste SARIMA")

3. Serie ampliada

ivae_h<-ts(as.numeric(rbind(as.matrix(pronosticos$x),as.matrix(pronosticos$mean))),start = c(2005,1),frequency = 12)
print(ivae_h)
##           Jan      Feb      Mar      Apr      May      Jun      Jul
## 2005  87.7700  88.5200  89.7200  91.1500  91.9800  92.6100  91.9400
## 2006  93.4800  93.5500  93.1700  93.5800  93.9100  94.2900  93.3700
## 2007  92.3700  94.9200  94.5100  94.3300  94.4500  95.3000  95.9400
## 2008  97.5700  97.7400  97.3100  96.8900  96.3500  96.6700  97.1500
## 2009  96.7500  95.1500  94.5500  93.9000  93.9500  94.5600  95.3400
## 2010  92.8400  92.2700  90.4200  90.2900  90.8200  91.6400  93.4800
## 2011  89.3100  89.8100  90.1400  89.9900  90.0500  89.1800  89.0200
## 2012  91.6400  92.6400  93.9600  95.5400  96.3700  95.8600  94.1500
## 2013  96.0400  96.2400  95.7700  95.5200  95.8100  96.0600  96.6300
## 2014  98.5000  98.7400  99.0400  98.9900  99.1800  99.7400  99.9400
## 2015 100.3600 100.1000 101.2600 102.6600 103.3500 103.4500 102.6900
## 2016 107.1800 107.0700 106.6100 107.6500 108.4200 108.7900 109.2900
## 2017 110.4600 110.8100 109.7200 109.6400 109.7000 109.2600 110.3200
## 2018 112.7600 112.7900 111.2800 110.9400 110.9800 110.6200 111.1600
## 2019 115.6000 116.0800 114.3000 114.4800 114.8800 114.4500 114.7300
## 2020 116.5333 116.8229                                             
##           Aug      Sep      Oct      Nov      Dec
## 2005  91.2600  92.2300  92.1600  92.3900  92.9700
## 2006  93.1000  93.0800  93.0400  93.1900  92.2400
## 2007  96.3800  97.0000  97.8100  98.2900  97.5100
## 2008  96.9900  97.7000  98.4900  98.5100  97.7900
## 2009  95.9000  96.3700  96.5300  96.8200  93.4100
## 2010  93.7100  92.0200  89.9200  88.8200  88.4700
## 2011  89.0600  88.9300  89.8100  90.6700  91.2200
## 2012  93.4400  93.2200  94.2700  95.3000  95.8100
## 2013  96.9500  97.3500  97.5100  97.8300  97.9000
## 2014 100.5100 100.9500 101.4500 101.6800 101.2900
## 2015 103.0200 103.8700 106.2900 107.5800 107.9900
## 2016 109.3500 109.5000 109.9900 110.2500 110.7200
## 2017 111.1200 111.2400 111.8300 112.3400 112.7400
## 2018 111.9700 112.6000 113.8600 114.3700 114.9400
## 2019 114.9800 115.2245 115.6874 115.9214 116.2002
## 2020

4. Descomposición de la serie temporal

library(stats)
fit<-stl(ivae_h,"periodic")
autoplot(fit)+theme_bw()

TC<-fit$time.series[,2]
print(TC)
##            Jan       Feb       Mar       Apr       May       Jun       Jul
## 2005  89.33065  89.69475  90.05884  90.40737  90.75589  91.10528  91.45468
## 2006  92.97505  93.12357  93.27209  93.33925  93.40642  93.38610  93.36579
## 2007  93.74450  94.03109  94.31768  94.71598  95.11427  95.51618  95.91808
## 2008  97.21051  97.25605  97.30160  97.32673  97.35186  97.33742  97.32298
## 2009  96.25643  96.06181  95.86720  95.70121  95.53521  95.34867  95.16212
## 2010  93.42337  93.09178  92.76020  92.37114  91.98209  91.62168  91.26127
## 2011  90.05301  89.84186  89.63071  89.60043  89.57015  89.68952  89.80890
## 2012  92.20839  92.69950  93.19062  93.57341  93.95621  94.25256  94.54890
## 2013  95.34121  95.58926  95.83731  96.08220  96.32708  96.52710  96.72713
## 2014  98.32469  98.63048  98.93627  99.24777  99.55927  99.81282 100.06636
## 2015 101.44406 101.71891 101.99377 102.37735 102.76094 103.28386 103.80678
## 2016 106.78568 107.24146 107.69723 108.03441 108.37159 108.64540 108.91922
## 2017 109.99292 110.09404 110.19515 110.32909 110.46304 110.63118 110.79932
## 2018 111.68363 111.74532 111.80701 111.90392 112.00083 112.18671 112.37258
## 2019 114.28663 114.52036 114.75410 114.88859 115.02309 115.13419 115.24529
## 2020 116.00865 116.15159                                                  
##            Aug       Sep       Oct       Nov       Dec
## 2005  91.80270  92.15072  92.38786  92.62500  92.80002
## 2006  93.35439  93.34299  93.39587  93.44874  93.59662
## 2007  96.23399  96.54990  96.76160  96.97330  97.09191
## 2008  97.21042  97.09785  96.89696  96.69607  96.47625
## 2009  94.92484  94.68757  94.38086  94.07415  93.74876
## 2010  91.03913  90.81698  90.65866  90.50033  90.27667
## 2011  90.03893  90.26897  90.69188  91.11479  91.66159
## 2012  94.73094  94.91298  94.99464  95.07630  95.20876
## 2013  96.95409  97.18104  97.45802  97.73499  98.02984
## 2014 100.25744 100.44852 100.67870 100.90889 101.17647
## 2015 104.33897 104.87115 105.34649 105.82182 106.30375
## 2016 109.17984 109.44045 109.61949 109.79853 109.89573
## 2017 110.98636 111.17340 111.33367 111.49395 111.58879
## 2018 112.66117 112.94977 113.29828 113.64680 113.96671
## 2019 115.36768 115.49008 115.61559 115.74110 115.87488
## 2020

5. Cálculo de las tasas (sin centrar)

library(dplyr)
library(zoo)
TC %>% as.numeric() %>% as.data.frame()->TC_df
names(TC_df)<-c("TC")
TC_df %>% mutate(T_1_1=(TC/dplyr::lag(TC,n=1)-1)*100,
                 T_1_12=(TC/dplyr::lag(TC,n=12)-1)*100,
                 T_12_12=(rollapply(TC,12,mean,align='right',fill=NA)
                          /rollapply(dplyr::lag(TC,n=12),12,mean,align='right',fill=NA)-1)*100) %>%
          #Aquí se realiza el centrado
          mutate(T_1_12C=dplyr::lead(T_1_12,n = 6),
                 T_12_12C=dplyr::lead(T_12_12,n = 12)) %>% ts(start = c(2005,1),frequency = 12)->tabla_coyuntura
print(tail(tabla_coyuntura,n=12))
##                TC      T_1_1   T_1_12  T_12_12  T_1_12C T_12_12C
## Mar 2019 114.7541 0.20409939 2.635866 1.837516 2.249066       NA
## Apr 2019 114.8886 0.11720402 2.667171 1.940907 2.045316       NA
## May 2019 115.0231 0.11706682 2.698421 2.049691 1.842816       NA
## Jun 2019 115.1342 0.09658822 2.627300 2.151287 1.674318       NA
## Jul 2019 115.2453 0.09649501 2.556415 2.245716 1.506763       NA
## Aug 2019 115.3677 0.10620600 2.402347 2.319794 1.424401       NA
## Sep 2019 115.4901 0.10609333 2.249066 2.373580       NA       NA
## Oct 2019 115.6156 0.10867507 2.045316 2.396324       NA       NA
## Nov 2019 115.7411 0.10855710 1.842816 2.388153       NA       NA
## Dec 2019 115.8749 0.11558319 1.674318 2.349155       NA       NA
## Jan 2020 116.0087 0.11544975 1.506763 2.279515       NA       NA
## Feb 2020 116.1516 0.12321171 1.424401 2.190472       NA       NA

6. Gráfico de las tasas (centradas)

library(dplyr)
library(forecast)
library(ggplot2)
tabla_coyuntura %>% as.data.frame() %>% select(T_1_12C,T_12_12C) %>% ts(start = c(2005,1),frequency = 12)->tabla_coyuntura_graficos
autoplot(tabla_coyuntura_graficos)+theme_bw()

tabla_coyuntura %>% as.data.frame() %>% select(T_1_1) %>% ts(start = c(2005,1),frequency = 12) %>% autoplot()